140 results on '"Rigamonti, Luca"'
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102. Synthesis, crystal structures and magnetic properties of dinuclear copper(ii) compounds with NNO tridentate Schiff base ligands and bridging aliphatic diamine and aromatic diimine linkers
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Rigamonti, Luca, primary, Forni, Alessandra, additional, Pievo, Roberta, additional, Reedijk, Jan, additional, and Pasini, Alessandro, additional
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- 2011
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103. The role of the atomic charges on the ligands and platinum(ii) in affecting the cis and trans influences in [PtXL(PPh3)2]+ complexes (X = NO3, Cl, Br, I; L = 4-substituted pyridines, amines, PPh3). A 31P NMR and DFT investigation
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Rigamonti, Luca, primary, Rusconi, Michele, additional, Forni, Alessandra, additional, and Pasini, Alessandro, additional
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- 2011
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104. Quantification of cis and trans influences in [PtX(PPh3)3]+ complexes. A 31P NMR study
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Rigamonti, Luca, primary, Rusconi, Michele, additional, Manassero, Carlo, additional, Manassero, Mario, additional, and Pasini, Alessandro, additional
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- 2010
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105. Cooperation between Cis and Trans Influences in cis-PtII(PPh3)2 Complexes: Structural, Spectroscopic, and Computational Studies
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Rigamonti, Luca, primary, Forni, Alessandra, additional, Manassero, Mario, additional, Manassero, Carlo, additional, and Pasini, Alessandro, additional
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- 2009
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106. cis Influence in trans-Pt(PPh3)2complexes
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Rigamonti, Luca, primary, Manassero, Carlo, additional, Rusconi, Michele, additional, Manassero, Mario, additional, and Pasini, Alessandro, additional
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- 2009
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107. Copper(II) Complexes of Tridentate Schiff Bases of 5‐Substituted Salicylaldehydes and Diamines – The Role of the Substituent and the Diamine in the Formation of Mono‐, Di‐ and Trinuclear Species – Crystal Structures and Magnetic Properties
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Rigamonti, Luca, primary, Cinti, Antonio, additional, Forni, Alessandra, additional, Pasini, Alessandro, additional, and Piovesana, Olivo, additional
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- 2008
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108. Experimental and Theoretical Studies on the Magnetic Anisotropy in Lanthanide(III)-Centered Fe3Ln Propellers.
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Rigamonti, Luca, Nava, Andrea, Boulon, Marie ‐ Emmanuelle, Luzon, Javier, Sessoli, Roberta, and Cornia, Andrea
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RARE earth metals , *MAGNETISM , *PARAMAGNETISM , *FERROMAGNETISM , *FERROMAGNETIC materials - Abstract
Compounds [Fe3Ln(tea)2(dpm)6] ( Fe3Ln; Ln= Tb-Yb, H3tea=triethanolamine, Hdpm=dipivaloylmethane) were synthesized as lanthanide(III)-centered variants of tetrairon(III) single-molecule magnets (Fe4) and isolated in crystalline form. Compounds with Ln=Tb-Tm are isomorphous and show crystallographic threefold symmetry. The coordination environment of the rare earth, given by two tea3− ligands, can be described as a bicapped distorted trigonal prism with D3 symmetry. Magnetic measurements showed the presence of weak ferromagnetic Fe ⋅⋅⋅Ln interactions for derivatives with Tb, Dy, Ho, and Er, and of weak antiferromagnetic or negligible coupling in complexes with Tm and Yb. Alternating current susceptibility measurements showed simple paramagnetic behavior down to 1.8 K and for frequencies reaching 10000 Hz, despite the easy-axis magnetic anisotropy found in Fe3Dy, Fe3Er, and Fe3Tm by single-crystal angle-resolved magnetometry. Relativistic quantum chemistry calculations were performed on Fe3Ln (Ln=Tb-Tm): the ground J multiplet of Ln3+ ion is split by the crystal field to give a ground singlet state for Tb and Tm, and a doublet for Dy, Ho, and Er with a large admixture of mJ states. Gyromagnetic factors result in no predominance of gz component along the threefold axis, with comparable gx and gy values in all compounds. It follows that the environment provided by the tea3− ligands, though uniaxial, is unsuitable to promote slow magnetic relaxation in Fe3Ln species. [ABSTRACT FROM AUTHOR]
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- 2015
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109. Redox-Controlled Exchange Bias in a Supramolecular Chain of Fe4 Single-Molecule Magnets.
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Nava, Andrea, Rigamonti, Luca, Zangrando, Ennio, Sessoli, Roberta, Wernsdorfer, Wolfgang, and Cornia, Andrea
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SINGLE molecule magnets , *IRON compounds , *MAGNETIZATION , *CHARGE exchange , *OXIDATION-reduction reaction - Abstract
Tetrairon(III) single-molecule magnets [Fe4(pPy)2(dpm)6] ( 1) (H3pPy=2-(hydroxymethyl)-2-(pyridin-4-yl)propane-1,3-diol, Hdpm=dipivaloylmethane) have been deliberately organized into supramolecular chains by reaction with RuIIRuII or RuIIRuIII paddlewheel complexes. The products [Fe4(pPy)2(dpm)6][Ru2(OAc)4](BF4)x with x=0 ( 2 a) or x=1 ( 2 b) differ in the electron count on the paramagnetic diruthenium bridges and display hysteresis loops of substantially different shape. Owing to their large easy-plane anisotropy, the s=1 diruthenium(II,II) units in 2 a act as effective seff=0 spins and lead to negligible intrachain communication. By contrast, the mixed-valent bridges ( s=3/2, seff=1/2) in 2 b introduce a significant exchange bias, with concomitant enhancement of the remnant magnetization. Our results suggest the possibility to use electron transfer to tune intermolecular communication in redox-responsive arrays of SMMs. [ABSTRACT FROM AUTHOR]
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- 2015
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110. Valence electronic structure of sublimated Fe4 single-molecule magnets: an experimental and theoretical characterization.
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Ninova, Silviya, Lanzilotto, Valeria, Malavolti, Luigi, Rigamonti, Luca, Cortigiani, Brunetto, Mannini, Matteo, Totti, Federico, and Sessoli, Roberta
- Abstract
The valence electronic structures of two single-molecule magnets (SMMs), [Fe
4 (L)2 (dpm)6 ] and [Fe4 (L)2 (pta)6 ], (Hdpm = dipivaloylmethane, Hpta = pivaloyltrifluoroacetone, L3− = Ph–C(CH2 O)3 3− ), are investigated by means of ultraviolet photoemission spectroscopy (UPS) and ab initio calculations. The experimental UPS spectra of both compounds are analysed and compared with the total density of states (TDOS) computed with the hybrid functional PBE0. The substitution of half of the methyl groups in [Fe4 (L)2 (dpm)6 ] with fluorine atoms in [Fe4 (L)2 (pta)6 ] unexpectedly affects the spectrum shape in the Fermi region, thus becoming a useful fingerprint of the two SMMs. Moreover, a computational protocol at DFT + U level of theory is assessed on both compounds, which is in good agreement with the experimental spectroscopic and magnetic data. The basis for the future modelling of the adsorption of Fe4 clusters on surfaces is established. [ABSTRACT FROM AUTHOR]- Published
- 2014
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111. Copper(II) Complexes of salen Analogues with Two Differently Substituted (Push−Pull) Salicylaldehyde Moieties. A Study on the Modulation of Electronic Asymmetry and Nonlinear Optical Properties
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Rigamonti, Luca, primary, Demartin, Francesco, additional, Forni, Alessandra, additional, Righetto, Stefania, additional, and Pasini, Alessandro, additional
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- 2006
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112. Enhanced Vapor-Phase Processing in Fluorinated Fe4 Single-Molecule Magnets.
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Rigamonti, Luca, Piccioli, Marco, Malavolti, Luigi, Poggini, Lorenzo, Mannini, Matteo, Totti, Federico, Cortigiani, Brunetto, Magnani, Agnese, Sessoli, Roberta, and Cornia, Andrea
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FLUORINATION , *IRON compounds , *SINGLE molecule magnets , *LIGANDS (Chemistry) , *ACETONE , *MOLECULAR self-assembly - Abstract
A new tetrairon(III) single-molecule magnet with enhanced volatility and processability was obtained by partial fluorination of the ancillary β-diketonato ligands. Fluorinated proligand Hpta = pivaloyltrifluoroacetone was used to assemble the bis(alkoxido)-bridged dimer [Fe2(OEt)2(pta)4] (1) in crystalline form, from which the new tetranuclear complex [Fe4(L)2(pta)6] (2) was synthesized in a one-pot reaction with H3L = 2-hydroxymethyl-2-phenylpropane-1,3-diol, NaOEt, and FeCl3 in a Et2O:EtOH solvent mixture. The structure of compound 2 was inferred from (1)H NMR, mass spectrometry, magnetic measurements, and DFT calculations. Direct current magnetic data are consistent with the expected metal-centered triangular topology for the iron(III) ions, with an antiferromagnetic coupling constant J = 16.20(6) cm-1 between the central iron and the peripheral ones and consequent stabilization of an S = 5 spin ground state. Alternating current (ac) susceptibility measurements in 0 and 1 kOe static applied fields show the presence of a thermally activated process for magnetic relaxation, with τ0 = 2.3(1) 10-7 s and Ueff/kB = 9.9(1) K at zero static field and τ0 = 2.0(2) 10-7 s and Ueff/kB = 13.0(2) K at 1 kOe. At a pressure of 10-7 mbar, compound 2 sublimates at (440 ± 5) K vs (500 ± 10) K for the nonfluorinated variant [Fe4(L)2(dpm)6] (Hdpm = dipivaloylmethane). According to XPS, ToF-SIMS, and ac susceptibility studies, the chemical composition, fragmentation pattern, and slow magnetic relaxation of the pristine material are retained in sublimated samples, suggesting that the molecular structure remains totally unaffected upon vapor-phase processing. [ABSTRACT FROM AUTHOR]
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- 2013
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113. Hydrogen Bonding Network of 4-Amidiniumpyridine Acetate and PtIIbis(triphenylphosphine) Complexes with 4-Amidinepyridine.
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Rigamonti, Luca, Carlino, Stefano, Castellano, Carlo, Demartin, Francesco, and Pasini, Alessandro
- Abstract
The X-ray structures of 4-amidiniumpyridine acetate, ( 1·H)AcO, and of cis-[Pt( 1)2(PPh3)2](NO3)2 ( 2), as well as their IR spectra, reveal intramolecular hydrogen bonding, which held together the cations and the anions. The IR spectroscopic data suggest that this may be so also in cis-[PtCl( 1)(PPh3)2](BF4) ( 3). In ( 1·H)AcO and in 2 extensive intermolecular hydrogen bonding networks span through the whole crystals. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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114. The role of the atomic charges on the ligands and platinum(ii) in affecting the cisand transinfluences in [PtXL(PPh3)2]+complexes (X = NO3, Cl, Br, I; L = 4-substituted pyridines, amines, PPh3). A 31P NMR and DFT investigationCCDC reference number 822142. For crystallographic data in CIF or other electronic format see DOI: 10.1039/c1dt10963d
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Rigamonti, Luca, Rusconi, Michele, Forni, Alessandra, and Pasini, Alessandro
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LIGANDS (Chemistry) , *ORGANOPLATINUM compounds , *TRANSITION metal complexes , *COUPLING constants , *FUNCTIONAL groups , *PYRIDINE , *DENSITY functionals , *WAVE functions , *QUANTUM theory - Abstract
One bond Pt–P coupling constants 1JPtPof a series of cationic complexes [PtXL(PPh3)2]+(X = NO3, Cl, Br, I; L = 4-Z-pyridines, Z = electron withdrawing or releasing groups, 4a–k; or X = Cl, L = NH3, PhCH2NH2and iPrNH2, 5a–c) have been used to establish the transand cisinfluence sequences of X and pyridines. The crystal structure of compound 4f(BF4) with Z = tBu has been resolved. In the pyridine complexes 4a–d(Z = H, variable X), both the transand cisinfluence series of the anionic ligands X decrease along the same sequence I > Br > Cl > NO3, as previously found for [PtX(PPh3)3]+(X = NO3, Cl, Br, I, 3a–d), however in 4a–dthe cisinfluence turns out to be more important than the trans. On the contrary, in [PtCl(4-Z-py)(PPh3)2]+(4b,e–k) the sequence of the transinfluence of the 4-Z-pyridines is opposite to that of the cis, the latter being Z = CN > CHO > Br > PhCO > H > Me > tBu > NH2, i.e.the most basic pyridine gives rise to the lowest cisinfluence. This correlation was found to hold also for complexes 5a–c(L = amines). All the observed trends have been fully reproduced by B3LYP/def2-SVP DFT calculations, by looking at the relevant optimized bond lengths of selected complexes of type 3, 4and 5. Subsequent evaluation of the atomic charges, by resorting to two independent methods, i.e., the Natural Bond Order analysis of the wavefunction and the Bader''s Quantum Theory of Atoms in Molecules, allowed for rationalization of the origin of the cisand transinfluences. The negative charge on the nitrogen atoms of free pyridines becomes more negative upon protonation and even more so when coordinated to the [PtCl(PPh3)2]+moiety. The least negatively charged nitrogen atom of coordinated pyridines is that of 4-CN-py (the highest cisinfluencing pyridine derivative), which gives rise to the lowest positive charge on Pt, confirming the relationship between the lowering of the charge on the metal ion and a high cisinfluence. The transinfluence can be described in terms of competition between the charges on the two transdonor atoms. In contrast with the behaviour of pyridines, the positive charge on the phosphorous atom of free PPh3increases upon coordination to Pt(ii), moreover the PPh3ligands acquire a substantial positive charge, thus efficiently delocalising the charge of the cationic complex. [ABSTRACT FROM AUTHOR]
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- 2011
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115. Quantification of cis and trans influences in [PtX(PPh3)3]+ complexes. A 31P NMR study
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Rigamonti, Luca, Rusconi, Michele, Manassero, Carlo, Manassero, Mario, and Pasini, Alessandro
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PLATINUM , *PHOSPHINE , *NUCLEAR magnetic resonance , *COUPLING constants , *CRYSTALS , *INORGANIC synthesis - Abstract
Abstract: In [PtX(PPh3)3]+ complexes (X=F, Cl, Br, I, AcO, NO3, NO2, H, Me) the mutual cis and trans influences of the PPh3 groups can be considered constants in the first place, therefore the one bond Pt–P coupling constants of P( cis ) and P( trans ) reflect the cis and trans influences of X. The compounds [PtBr(PPh3)3](BF4) (2), [PtI(PPh3)3](BF4) (3), [Pt(AcO)(PPh3)3](BF4) (4), [Pt(NO3)(PPh3)3](BF4) (5), and the two isomers [Pt(NO2-O)(PPh3)3](BF4) (6a) and [Pt(NO2-N)(PPh3)3](BF4) (6b) have been newly synthesised and the crystal structures of 2 and 4·CH2Cl2·0.25C3H6O have been determined. From the 1 J PtP values of all compounds we have deduced the series: I>Br>Cl>NO3 >ONO>F>AcO>NO2 >H>Me (cis influence) and Me>H>NO2 >AcO>I>ONO>Br>Cl>F>NO3 (trans influence). These sequences are like those obtained for the (neutral) cis- and trans-[PtClX(PPh3)2] derivatives, showing that there is no dependence on the charge of the complexes. On the contrary, the weights of both influences, relative to those of X=Cl, were found to depend on the charge and nature of the complex. [ABSTRACT FROM AUTHOR]
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- 2010
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116. Cooperation between Cis and Trans Influences in cis-PtII(PPh3)2 Complexes: Structural, Spectroscopic, and Computational Studies.
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Rigamonti, Luca, Forni, Alessandra, Manassero, Mario, Manassero, Carlo, and Pasini, Alessandro
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X-ray crystallography , *PHOSPHINE , *COUPLINGS (Gearing) , *LIGANDS (Chemistry) , *DENSITY functionals , *SPECTRUM analysis - Abstract
The relevance of cix and trans influences of some anionic ligands X and V in cis-[PtX2(PPh3)2] and cis-[PIXY(PPh3)2] complexes have been studied by Ihe X-ray crystal structures of several derivatives (X2 = (AcO)2 (3), (NO3)2 (5), Br2 (7), I2(11); and XV = Cl(AcO) (2), ClNO3) (4), and CI(NO2) (13)), density functional theory (DFT) calculations, and one bond Pt-P coupling constants, J. The latter have allowed an evaluation of the relative magnitude of both influences. It is concluded that such influences act in a cooperative way and that the cis influence is not irrelevant when rationalizing the 1JPIP values, as well as the experimental Pt-P bond distances. On the contrary, in the optimized geometries, evaluated through B3LVP/def2-SVP calculations, the cis influence was not observed, except for compounds CIPh (21), Ph2 (22), and, to a lesser extent, Cl(NO2) (13) and (NO2)2 (14). A natural bond order analysis on the optimized structures, however, has shown how the cis influence can be related to the s-character of the Pt hybrid orbital involved in the Pt-P bonds and the net atomic charge on Pt. We have also found that in the X-ray structures of cis-[PIX2(PPh3)2] complexes the two Pt-X and the two Pt-P bond lengths are different each other and are related to the conformation of the phosphine groups, rather than to the crystal packing, since this lealure is observed also in the optimized geometries. [ABSTRACT FROM AUTHOR]
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- 2010
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117. cis Influence in trans-Pt(PPh3)2 complexes.
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Rigamonti, Luca, Manassero, Carlo, Rusconi, Michele, Manassero, Mario, and Pasini, Alessandro
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PLATINUM compounds , *METAL complexes , *LIGANDS (Chemistry) , *MOLECULAR structure , *COUPLING constants , *CHEMICAL formulas - Abstract
The cis influence of a series of anionic ligands X and Y has been evaluated through the magnitude of the Pt-P coupling constants for compounds of formula trans-[PtXY(PPh3)2]. The order of decreasing cis influence was found to be I > Cl > SePh ∼ SPh ∼ SEt > NO3 > AcO ∼ NO2 > H > Me > Ph > mtc (mtc = N,N-dimethylmonothiocarbamato-S); moreover, the cis influences of the various ligands was found to be additive. The X-ray structures of three representative compounds (t-4: X = Cl, Y = NO3; t-5: X = Cl, Y = AcO and t-12: X = Y = NO2) have also been determined. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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118. cisInfluence in trans-Pt(PPh3)2complexesCCDC reference numbers 695960–695962. For crystallographic data in CIF or other electronic format see DOI: 10.1039/b813125bDedicated to Prof. Renato Ugo on the occasion of his 70th birthday.
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Rigamonti, Luca, Manassero, Carlo, Rusconi, Michele, Manassero, Mario, and Pasini, Alessandro
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PLATINUM compounds ,METAL complexes ,CRYSTALLOGRAPHY ,LIGANDS (Chemistry) ,CHEMICAL structure ,COUPLING constants - Abstract
The cisinfluence of a series of anionic ligands X and Y has been evaluated through the magnitude of the Pt–P coupling constants for compounds of formula trans-[PtXY(PPh3)2]. The order of decreasing cisinfluence was found to be I > Cl > SePh ∼ SPh ∼ SEt > NO3> AcO ∼ NO2> H > Me > Ph > mtc (mtc = N,N-dimethylmonothiocarbamato-S); moreover, the cisinfluences of the various ligands was found to be additive. The X-ray structures of three representative compounds (t-4: X = Cl, Y = NO3; t-5: X = Cl, Y = AcO and t-12: X = Y = NO2) have also been determined. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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119. CopperII Complexes of Tridentate Schiff Bases of 5Substituted Salicylaldehydes and Diamines – The Role of the Substituent and the Diamine in the Formation of Mono, Di and Trinuclear Species – Crystal Structures and Magnetic Properties
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Rigamonti, Luca, Cinti, Antonio, Forni, Alessandra, Pasini, Alessandro, and Piovesana, Olivo
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We describe some copperII complexes with tridentate anionic Schiff bases, L–, derived from the monocondensation of some 5substituted salicylaldehydes 5GsalH, G = H, NO2and OMe with ethylenediamine en or 1,3diaminopropane tn. Mononuclear [CuLpy]+, dinuclear [Cu2L2]2+and trinuclear [Cu3L3μ3OH]2+compounds have been obtained, and factors affecting the nuclearity of complexes were investigated and found to depend on reaction conditions, the nature of G and the length of the diamine. The crystal structures of seven representative compounds have been determined. Magnetic studies on a dinuclear and a trinuclear species were also carried out, and the results were interpreted on the basis of the structural data and current superexchange models. © WileyVCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008
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- 2008
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120. Selective Formation, Reactivity, Redox and Magnetic Properties of Mn III and Fe III Dinuclear Complexes with Shortened Salen-Type Schiff Base Ligands.
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Rigamonti, Luca, Zardi, Paolo, Carlino, Stefano, Demartin, Francesco, Castellano, Carlo, Pigani, Laura, Ponti, Alessandro, Ferretti, Anna Maria, and Pasini, Alessandro
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SCHIFF bases , *MAGNETIC properties , *BRIDGING ligands , *LIGANDS (Biochemistry) , *COUPLING constants - Abstract
The reactivity of the shortened salen-type ligands H3salmp, H2salmen and H2sal(p-X)ben with variable para-substituent on the central aromatic ring (X = tBu, Me, H, F, Cl, CF3, NO2) towards the trivalent metal ions manganese(III) and iron(III) is presented. The selective formation of the dinuclear complexes [M2(μ-salmp)2], M = Mn (1a), Fe (2a), [M2(μ-salmen)2(μ-OR)2)], R = Et, Me, H and M = Mn (3a–c) or Fe (4a–c), and (M2(μ-sal[p-X]ben)2(μ-OMe)2), X = tBu, Me, H, F, Cl, CF3, NO2 and M = Mn (5a–g) or Fe (6a–g), could be identified by reaction of the Schiff bases with metal salts and the base NEt3, and their characterization through elemental analysis, infrared spectroscopy, mass spectrometry and single-crystal X-ray diffraction of 2a·2AcOEt, 2a·2CH3CN and 3c·2DMF was performed. In the case of iron(III) and H3salmp, when using NaOH as a base instead of NEt3, the dinuclear complexes [Fe2(μ-salmp)(μ-OR)(salim)2], R = Me, H (2b,c) could be isolated and spectroscopically characterized, including the crystal structure of 2b·1.5H2O, which showed that rupture of one salmp3− to two coordinated salim− ligands and release of one salH molecule occurred. The same hydrolytic tendency could be identified with sal(p-X)ben ligands in the case of iron(III) also by using NEt3 or upon standing in solution, while manganese(III) did not promote such a C–N bond breakage. Cyclic voltammetry studies were performed for 3b, 4b, 5a and 6a, revealing that the iron(III) complexes can be irreversibly reduced to the mixed-valence FeIIFeIII and FeII2 dinuclear species, while the manganese(III) derivatives can be reversibly oxidized to either the mixed-valence MnIIIMnIV or to the MnIV2 dinuclear species. The super-exchange interaction between the metal centers, mediated by the bridging ligands, resulted in being antiferromagnetic (AFM) for the selected dinuclear compounds 3b, 4b, 5a, 5e,5f, 6a and 6e. The coupling constants J (–2JŜ1·Ŝ2 formalism) had values around −13 cm−1 for manganese(III) compounds, among the largest AFM coupling constants reported so far for dinuclear MnIII2 derivatives, while values between −3 and −10 cm−1 were obtained for iron(III) compounds. [ABSTRACT FROM AUTHOR]
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- 2020
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121. Physical clinical care and artificial-intelligence-guided core resistance training improve endurance and patient-reported outcomes in subjects with lower back pain.
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Bates, Nathaniel A., Huffman, Allison, Goodyear, Evelyn, Nagai, Takashi, Rigamonti, Luca, Breuer, Logan, Holmes, Benjamin D., and Schilaty, Nathan D.
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LUMBAR pain , *RESISTANCE training , *THERAPEUTICS , *COMPUTERS in medicine , *CHRONIC pain , *LABOR productivity , *ENDURANCE sports training , *TIME , *ARTIFICIAL intelligence , *PHYSICAL fitness , *HEALTH outcome assessment , *PATIENT satisfaction , *RANDOMIZED controlled trials , *COMPARATIVE studies , *FUNCTIONAL assessment , *QUALITY of life , *ABDOMINAL exercises , *STATISTICAL sampling , *BACK exercises , *PAIN management , *EVALUATION - Abstract
Low back pain is an extremely prevalent issue with an extensive impact, ranging from decreased quality of life to lost years of productivity. Many interventions have been developed to alleviate chronic lower back pain, yet it remains a widespread problem. The objective of this study was to examine the role of artificial intelligence guided resistance training relative to clinical variables in subjects experiencing lower back pain. 69 out of 108 enrolled and 92 accrued subjects completed the 8-week intervention. Subjects were randomized into four groups (Control, Training, Clinical, or Combined). The Training cohort received supervised artificial-intelligence-guided core-focused resistance training while the Clinical group received clinical care. The Combined group received both clinical care and artificial-intelligence-guided training and the Control group received no treatment. Participants were evaluated using functional testing and patient-reported outcomes at baseline, 4 weeks, and 8 weeks. In the clinical tests, the Clinical and Combined cohorts showed increased total time for isometric extensor endurance and the Clinical cohort increased total distance traveled in the 6-min walk test at 8 weeks. The Training, Clinical, and Combined groups showed improvements in Patient-reported outcomes after 8 weeks. Most of the significant improvements were only seen at the 8-week evaluation for both the clinical evaluations and Patient-reported outcomes. The Control group did not show significant improvements in any outcome measures. The present data indicate that core-focused interventions, including artificial-intelligence-guided moderate-resistance exercise, can increase objective functional outcomes and patient satisfaction using Patient-reported outcomes in individuals with lower back pain. • Low back pain continues to be a major cost and disability burden on the medical community. • Artificial intelligence guided exercise improved function and outcomes in low back pain patients. • Control patients failed to exhibit improvements over the 8-week period. • Artificial intelligence guided exercise offers a supplement to clinical care for low back pain. [ABSTRACT FROM AUTHOR]
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- 2023
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122. When the metal makes the difference: template syntheses of tridentate and tetradentate salen-type schiff base ligands and related complexes
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Rita Mazzoni, Luca Rigamonti, Fabrizio Roncaglia, Mazzoni, Rita, Roncaglia, Fabrizio, and Rigamonti, Luca
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metal coordination ,aliphatic diamine ,General Chemical Engineering ,Crystal structure ,010402 general chemistry ,01 natural sciences ,transition metals ,Adduct ,Inorganic Chemistry ,chemistry.chemical_compound ,Transition metal ,Diamine ,Polymer chemistry ,General Materials Science ,Reactivity (chemistry) ,oligonuclear complexes ,oligonuclear complexe ,Lone pair ,Metal coordination ,Salicylaldehyde ,Schiff base ligands ,Crystallography ,Schiff base ,Imine formation ,010405 organic chemistry ,Template effect ,Aliphatic diamine ,Schiff base ligand ,Transition metals ,Oligonuclear complexes ,salicylaldehyde ,Condensed Matter Physics ,0104 chemical sciences ,chemistry ,QD901-999 ,imine formation ,template effect - Abstract
The reaction of organic molecules mediated by a metal center (template synthesis) can result in a final connectivity that may differ from the one obtained in the absence of the metal. The condensation of carbonyl fragments with primary amines form C=N iminic bonds, the so-called Schiff bases, which can act as ligands for the templating metal center by means of the lone pair on the nitrogen atom. This review focuses on the template methods for the reaction between a carbonyl compound (mainly salicylaldehyde) and a primary aliphatic diamine able to prevent the double condensation on both amine groups and obtain tridentate N2O ligands. These adducts, still having one free amino group, can further react, yielding tetradentate salen-type Schiff base ligands. A screening over the transition metals able to show such a template effect will be presented, with particular attention to copper(II), together with their peculiar reactivity and the available crystal structure of the metal complexes and related coordination geometries.
- Published
- 2021
123. Redox-Controlled Exchange Bias in a Supramolecular Chain of Fe4Single-Molecule Magnets
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Andrea Nava, Ennio Zangrando, Wolfgang Wernsdorfer, Luca Rigamonti, Andrea Cornia, Roberta Sessoli, Department of Chemistry 'Ugo Schiff', Università degli Studi di Firenze = University of Florence [Firenze] (UNIFI), Circuits électroniques quantiques Alpes (QuantECA), Institut Néel (NEEL), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS), Nava, Andrea, Rigamonti, Luca, Zangrando, Ennio, Sessoli, Roberta, Wernsdorfer, Wolfgang, and Cornia, Andrea
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Chain structure ,Iron ,Supramolecular chemistry ,Ruthenium ,Catalysis ,Paramagnetism ,chemistry.chemical_compound ,Magnetization ,Electron transfer ,Nuclear magnetic resonance ,Magnetic properties ,Molecule ,Hydroxymethyl ,Single-molecule magnet ,ComputingMilieux_MISCELLANEOUS ,[PHYS]Physics [physics] ,Chain structures ,Single-molecule magnets ,Chemistry (all) ,Intermolecular force ,chain structures ,iron ,magnetic properties ,ruthenium ,single-molecule magnets ,General Chemistry ,General Medicine ,3. Good health ,Crystallography ,Exchange bias ,chemistry ,Magnetic propertie - Abstract
Tetrairon(III) single-molecule magnets [Fe4(pPy)2(dpm)6] (1) (H3pPy=2-(hydroxymethyl)-2-(pyridin-4-yl)propane-1,3-diol, Hdpm=dipivaloylmethane) have been deliberately organized into supramolecular chains by reaction with Ru(II)Ru(II) or Ru(II)Ru(III) paddlewheel complexes. The products [Fe4(pPy)2(dpm)6][Ru2(OAc)4](BF4)x with x=0 (2 a) or x=1 (2 b) differ in the electron count on the paramagnetic diruthenium bridges and display hysteresis loops of substantially different shape. Owing to their large easy-plane anisotropy, the s=1 diruthenium(II,II) units in 2 a act as effective s(eff)=0 spins and lead to negligible intrachain communication. By contrast, the mixed-valent bridges (s=3/2, s(eff)=1/2) in 2 b introduce a significant exchange bias, with concomitant enhancement of the remnant magnetization. Our results suggest the possibility to use electron transfer to tune intermolecular communication in redox-responsive arrays of SMMs.
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- 2015
124. Pediatric meniscal surgery in Italy: A 10-year epidemiological nationwide registry study.
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Riganti A, Bigoni M, Pierpaoli E, Caliandro M, Piscitelli D, Nicolaou N, Rigamonti L, and Turati M
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Purpose: Over the last two decades the incidence of meniscal injuries has grown amongst the pediatric population predominantly due to greater involvement in sporting activities. The treatment and the natural history represent a socioeconomic burden for healthcare systems. This study demonstrates the epidemiology of meniscal tears treated surgically in Italy from 2010 to 2019 in a population up to 18 years., Methods: Data was collected from the National Archive of Hospital Discharges. ICD9-CM classification was used to select surgically treated meniscal injuries. Concomitant treatment of associated lesions were excluded. Data on the national population was retrieved from the Italian National Institute for Statistics (ISTAT). Statistical analyses were performed., Results: 17,449 isolated meniscal tears were surgically treated with a mean incidence of 20.6 per 100.000 in the Italian population aged up to 18 from 2010 to 2019. The mean age of patients was 15.85 with 89 % aged 14 or older. 30 % of the population was female. The incidence of medial meniscal surgery was higher than for the lateral meniscus. A declining trend in surgical incidence was observed. The mean hospitalization time was 1.53 days., Conclusions: Our study reveals a reduction in the total number of surgeries performed over the time frame and a significant rise in the incidence of meniscal lesions in pediatric patient above at the age of 13, especially in males. Despite a worldwide shift towards meniscal preservation, this trend is not evident in Italy as the current ICD9-CM classification does not differentiate between meniscectomy and meniscal repair, although an overall reduction in surgery may imply better management., Study Design: Cohort study; Level of evidence III., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 Published by Elsevier Ltd.)
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- 2024
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125. Light on the sustainable preparation of aryl-cored dibromides.
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Roncaglia F, Ughetti A, Porcelli N, Anderlini B, Severini A, and Rigamonti L
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Both aryl and benzyl polybromides have gained significant importance as reactive building blocks in polymer and materials chemistry. Their preparation primarily relies on established synthetic methods using molecular bromine or N -bromosuccinimide, known for their reliability and effectiveness. However, from a sustainability perspective, these methods suffer from the generation of stoichiometric amounts of byproducts and often encounter selectivity troubles. To mitigate these issues, we extended the greener peroxide-bromide halogenation method, initially developed for monobromides, to afford aryl-cored polybromides in high yields. The same method can be employed in two variants modulated by light irradiation. This external switch can be used to selectively trigger side-chain or core halogenation., (Copyright © 2024, Roncaglia et al.)
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- 2024
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126. Arthroscopic repair of proximal anterior cruciate ligament tears in children and adolescents: A systematic review.
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Turati M, Anghilieri FM, Gatti SD, Courvoisier A, Rigamonti L, Zatti G, Nicolaou N, and Bigoni M
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Purpose: Anterior cruciate ligament repair techniques are of growing interest because they allow for minimally invasive surgery that avoids harvesting of the transplant, without risking growth deficiencies in young patients. The aim of this study is to summarize the published evidence about arthroscopic repair of anterior cruciate ligament proximal tears in skeletally immature patients., Methods: In total, four studies were included and processed for data extraction after screening for eligibility for this systematic review: one retrospective cohort study and three retrospective case series. Altogether, the four studies included in this review included 61 skeletally immature patients with a mean age of 12.1 years diagnosed with proximal anterior cruciate ligament tear who underwent arthroscopic repair with preservation of the native ligament. The mean follow-up period was 2.8 years., Results: The most relevant and objective outcome that we considered was re-rupture rate. One study reports a cumulative incidence of graft failure in the first 3 years after surgery of 48.8% while the others report a 0%, 0% and 21.5% re-rupture rate. No growth disturbances were reported in the included studies., Conclusion: Despite growing interest surrounding anterior cruciate ligament repair techniques, the presence of limited quality studies in the literature means repair cannot be strongly supported at present. Some encouraging data regarding the absence of growth disturbance and functional outcomes does exist, but studies with larger samples are required., Level of Evidence: level IV., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2024.)
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- 2024
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127. Management of anterior cruciate ligament tears in Tanner stage 1 and 2 children: a narrative review and treatment algorithm guided by ACL tear location.
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Turati M, Rigamonti L, Giulivi A, Gaddi D, Accadbled F, Zanchi N, Bremond N, Catalano M, Gorla M, Omeljaniuk RJ, Zatti G, Piatti M, and Bigoni M
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- Humans, Child, Magnetic Resonance Imaging, Rupture surgery, Algorithms, Retrospective Studies, Anterior Cruciate Ligament Injuries diagnostic imaging, Anterior Cruciate Ligament Injuries surgery, Anterior Cruciate Ligament Reconstruction methods
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The incidence of anterior cruciate ligament (ACL) tears in skeletally immature patients has acutely increased over the last 20 years, yet there is no consensus on a single "best treatment." Selection of an optimal treatment is critical and based on individual circumstances; consequently, we propose a treatment-selection algorithm based on skeletal development, ACL tear location, type, and quality, as well as parental perspective in order to facilitate the decision-making process. We combined our surgical group's extensive case histories of ACL tear management in Tanner Stage 1 and 2 patients with those in the literature to form a consolidated data base. For each case the diagnostic phase, communication with patient and parents, treatment choice(s), selected surgical techniques and rehabilitation schedule were critically analyzed and compared for patient outcomes. MRI-imaging and intraoperative tissue quality assessment were preeminent in importance for selection of the optimal treatment strategy. Considerations for selecting an optimal treatment included: associated lesions, the child/patient and parent(s)' well-informed and counseled consent, biological potential, and the potential for successful ACL preservative surgery. Complete ACL tears were evaluated according to tear-location. In type I and II ACL tears with remaining good tissue quality, we propose primary ACL repair. In type III and IV ACL tears we propose physeal-sparing reconstruction with an iliotibial band graft. Finally, in the case of a type V ACL tear, we propose that the best treatment be based on the Meyers-McKeever classification. We present a facile decision-making algorithm for ACL management in pediatric patients based on specific elements of tissue damage and status.
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- 2023
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128. Effects of neuromuscular and proprioceptive training on self-reported wellness and health scores and knee sensorimotor characteristics in active seniors.
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Nagai T, Bates NA, Rigamonti L, Hollman JH, Laskowski ER, and Schilaty ND
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- Humans, Self Report, Knee, Exercise Therapy methods, Lower Extremity, Frailty
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Introduction: Athletes regularly engage in comprehensive neuromuscular and proprioceptive training (NPT) to prevent musculoskeletal (MSK) injuries. NPT exercises such as movement technique, agility, balance, and posture as well as yoga-based stretching and slow/deep breathing have shown added benefits in psychological and other well-being. This study aimed to examine the effects of NPT on knee sensorimotor characteristics and multi-domain wellness and health scores in active seniors., Methods: Twenty seniors participated in the NPT intervention (15-20min session twice a week for 10 weeks) while the control group did not receive any intervention. All participants completed surveys (general health, frailty, anxiety, stress, mindfulness, optimism, and sleep quality) and laboratory testing before and after intervention. Laboratory testing included frailty tests (grip strength, 4-m walk speed, and calcaneal ultrasound-based bone density) and knee sensorimotor characteristics (peak force, visual-motor reaction time, and force steadiness)., Results: There was significant increase in general mental health (Short Form 36 Mental Health; p = 0.005) and decrease in stress (Perceived Stress Scale; p = 0.010) and sleep disturbances (Pittsburgh Sleep Quality Index; p = 0.019) post-intervention while no significant changes were observed in the control group (p = 0.310-0.654). Peak knee forces in all directions and some visual-motor reaction time and force steadiness were significantly improved post-intervention only in the experimental group (p = 0.001-0.038)., Conclusion: A simple, yet, comprehensive NPT has potential to improve MSK health as well as various domains of well-being among active seniors., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2023. Published by Elsevier Ltd.)
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- 2023
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129. The effectiveness of clinic versus home-based, artificial intelligence-guided therapy in patients with low back pain: Non-randomized clinical trial.
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Alzouhayli K, Schilaty ND, Nagai T, Rigamonti L, McPherson AL, Holmes B, and Bates NA
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- Humans, Male, Female, Artificial Intelligence, Treatment Outcome, Exercise Therapy methods, Exercise, Low Back Pain therapy
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Background: Low back pain is a common cause of disability in the US with increasing financial burden on healthcare. A variety of treatment options exist to combat LBP. Home-based therapy is a low-cost option, but there is a lack of data on how it compares to therapy in clinical settings. It was hypothesized that when using artificial intelligence-guided therapy, supervised in-clinic interventions would have a greater influence on patient-reported outcomes and strength than unsupervised, home interventions., Methods: This is a non-randomized controlled trial of 51 patients (28 female, 23 male). The investigation compared an 8-week, core-focused exercise intervention in a Clinic (supervised) versus Home (unsupervised) setting. Outcome variables included measures of strength, performance, and patient-reported outcomes related to function. Generalized linear regression (p < 0.05) was used to evaluate outcomes were evaluated with respect to sex, intervention setting, and time., Findings: Male subjects exhibited greater strength (p ≤ 0.02) but not greater patient-reported outcomes (p ≥ 0.30) than females. The Clinic group exhibited slightly greater lateral pull-down strength (p = 0.002), greater eccentric phase range of motion during overhead press (p < 0.01), and shorter concentric phase duration during bench press (p < 0.01) than the Home group. Significance between groups was not observed in any other strength, performance, or patient-reported outcome (p ≥ 0.11)., Interpretation: A lack of consistent significance indicated that the hypothesis was not supported. AI-guided, telehealth exercise produced comparable outcomes in both home and clinical settings. Telehealth options may offer a lower-cost alternative to clinic-based exercise therapy for patients with nonspecific lower back pain., Competing Interests: Declaration of Competing Interest There was no conflict of interest in the preparation of this manuscript., (Copyright © 2023 Elsevier Ltd. All rights reserved.)
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- 2023
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130. Development of Stable Amino-Pyrimidine-Curcumin Analogs: Synthesis, Equilibria in Solution, and Potential Anti-Proliferative Activity.
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Mari M, Boniburini M, Tosato M, Rigamonti L, Cuoghi L, Belluti S, Imbriano C, Avino G, Asti M, and Ferrari E
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- Male, Humans, Biological Availability, Antihypertensive Agents, Antimetabolites, Cell Survival, Curcumin pharmacology
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With the clear need for better cancer treatment, naturally occurring molecules represent a powerful inspiration. Recently, curcumin has attracted attention for its pleiotropic anticancer activity in vitro, especially against colorectal and prostate cancer cells. Unfortunately, these encouraging results were disappointing in vivo due to curcumin's low stability and poor bioavailability. To overcome these issues, herein, the synthesis of eight new pyrimidine-curcumin derivatives is reported. The compounds were fully characterized (
1 H/13 C NMR (Nuclear Magnetic Resonance), LC-MS (Liquid Chromatography-Mass Spectrometri), UV-Vis spectroscopy), particularly their acid/base behavior; overall protonation constants were estimated, and species distribution, as a function of pH, was predicted, suggesting that all the compounds are in their neutral form at pH 7.4. All the compounds were extremely stable in simulated physiological media (phosphate-buffered saline and simulated plasma). The compounds were tested in vitro (48 h incubation treatment) to assess their effect on cell viability in prostate cancer (LNCaP and PC3) and colorectal cancer (HT29 and HCT116) cell lines. Two compounds showed the same anti-proliferative activity as curcumin against HCT116 cells and improved cytotoxicity against PC3 cells.- Published
- 2023
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131. Clinical outcomes and complications after anterior cruciate ligament reconstruction with bone-patellar tendon-bone in patient Tanner 3 and 4: a systematic review.
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Turati M, Caliandro M, Gaddi D, Piatti M, Rigamonti L, Zanchi N, Di Benedetto P, Boerci L, Catalano M, Zatti G, Ollivier M, and Bigoni M
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- Humans, Adolescent, Bone-Patellar Tendon-Bone Grafting adverse effects, Bone-Patellar Tendon-Bone Grafting methods, Anterior Cruciate Ligament surgery, Transplantation, Autologous, Anterior Cruciate Ligament Reconstruction adverse effects, Anterior Cruciate Ligament Reconstruction methods, Patellar Ligament transplantation, Anterior Cruciate Ligament Injuries surgery
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Background: Clinical outcomes and potential complications associated with Bone-Patellar Tendon-Bone (BPTB) graft in skeletally immature ACL reconstruction (ACLR) are poorly defined. Considering that in Tanner 1-2 patients this kind of graft is not recommended, we focused our systematic review on the evaluation of all the studies in the literature that reported clinical outcomes and rate of complications of the ACLR using BPTB graft in Tanner 3-4 patients., Methods: This review was conducted in accordance with the PRISMA statement. PubMed, Cochrane Library, EMBASE and Scopus were examined from 1965 to 2020 using different combinations of the following keywords: "ACL reconstruction", "skeletally immature", "young", "patellar tendon" and "BPTB". The database search yielded 742 studies, on which we performed a primary evaluation. After carrying out a full-text evaluation for the inclusion criteria, 4 studies were included in the final review and assessed using the Newcastle-Ottawa scale. Ninety-six cases with mean age of 14.2 years were reported., Results: Good stability and functional outcomes were reported with a mean follow-up of 49.5 months. Return to sport rate ranged from 91.7% to 100%. A KT-1000 side-to-side difference higher than 5 mm was observed in five patients (5.2%). No lower limb length discrepancy and angulation were reported. Graft rupture rate was 5.2%., Conclusion: According to these results, BTPB graft could be a good choice in Tanner 3-4 patients who want to achieve their preinjury sport level with a low risk of growth disturbances and graft failure. Further investigations in a wider population are needed., (© 2022. The Author(s).)
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- 2023
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132. A proficient multivariate approach for iron(II) spin crossover behaviour modelling in the solid state.
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Marchi L, Fantuzzi S, Cingolani A, Messori A, Mazzoni R, Zacchini S, Cocchi M, and Rigamonti L
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Iron(II) bis -pyrazolilpyridyl (bpp-R) complexes [Fe(bpp-R)
2 ](X)2 ·solvent, R = substituent and X- = anion, can undergo a spin transition from high ( S = 2, HS) to low spin ( S = 0, LS), being spin crossover (SCO) in the solid state. The distortion of the octahedral coordination environment around the metal centre is governed by crystal packing, i.e. the intermolecular interactions among the substituent R of the bpp-R ligands, the anion X- , and the co-crystallized solvent, and this modulates the SCO behaviour. In this work, an innovative multivariate approach, through the combination of the chemometric tools Principal Component Analysis and Partial Least Squares regression, was applied on the coordination bond distances and angles and selected torsional angles of the available HS structures. The obtained results can efficiently model and rationalize the structural data distinguishing between SCO-active and HS-blocked complexes bearing different R groups, X- anions, and co-crystallized solvents and help predict the spin transition temperature T1/2 .- Published
- 2023
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133. Comparison of all-suture anchors with metallic anchors in arthroscopic cuff repair: Structural and functional properties and clinical suitability.
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Piatti M, Gorla M, Alberio F, Omeljaniuk RJ, Rigamonti L, Gaddi D, Turati M, and Bigoni M
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Purpose: This study examined and compared all-suture anchors with metallic anchors in the arthroscopic repair of small to medium supraspinatus tears; a multi-dimensional evaluation protocol assessed (i) clinical, (ii) ultrasonographical, and (iii) functional criteria at mid-term., Materials and Methods: A sample of 40 patients, prescreened from a larger group who had undergone arthroscopic rotator cuff repair, were resolved into two groups of 20, based on the type of anchor used in their surgery (all-suture or metallic) and were evaluated postoperatively (mean = 44.3 months, SEM = 22.4 months, minimum period = 10.3 months). Clinical assessments included (i) objective and subjective scores (Constant, DASH, SPADI, SST), (ii) ultrasonographical examination, as well as (iii) isometric and isokinetic strength testing. Raw data from the operated side was compared with those from the contralateral side within each group. Raw data for the PROMs and for the US evaluation were compared between groups. Strength data, as well as the Constant score values, were further analyzed based on (i) the difference between operated and intact sides, as well as (ii) the strength ratio between operated and intact sides; the transformed data were then compared between the two groups., Results: We found no statistically significant differences in any of the parameters considered between shoulders operated using ASAs or MAs, nor between operated and non-operated sides in each group., Conclusion: Our findings indicate that the reliability and performance characteristics of all-suture anchors and metallic anchors are practically indistinguishable for arthroscopic treatment of small to medium lesions of the supraspinatus tendon., Competing Interests: None., (© 2023 Professor P K Surendran Memorial Education Foundation. Published by Elsevier B.V. All rights reserved.)
- Published
- 2023
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134. Flow-dependent shear stress affects the biological properties of pericyte-like cells isolated from human dental pulp.
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Bertani G, Di Tinco R, Bertoni L, Orlandi G, Pisciotta A, Rosa R, Rigamonti L, Signore M, Bertacchini J, Sena P, De Biasi S, Villa E, and Carnevale G
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- Humans, Dental Pulp, Leukocytes, Mononuclear, Stem Cells, Pericytes, Endothelial Cells
- Abstract
Background: Human dental pulp stem cells represent a mesenchymal stem cell niche localized in the perivascular area of dental pulp and are characterized by low immunogenicity and immunomodulatory/anti-inflammatory properties. Pericytes, mural cells surrounding the endothelium of small vessels, regulate numerous functions including vessel growth, stabilization and permeability. It is well established that pericytes have a tight cross talk with endothelial cells in neoangiogenesis and vessel stabilization, which are regulated by different factors, i.e., microenvironment and flow-dependent shear stress. The aim of this study was to evaluate the effects of a pulsatile unidirectional flow in the presence or not of an inflammatory microenvironment on the biological properties of pericyte-like cells isolated from human dental pulp (hDPSCs)., Methods: Human DPSCs were cultured under both static and dynamic conditions with or without pre-activated peripheral blood mononuclear cells (PBMCs). Pulsatile unidirectional flow shear stress was generated by using a specific peristaltic pump. The angiogenic potential and inflammatory properties of hDPSCs were evaluated through reverse phase protein microarrays (RPPA), confocal immunofluorescence and western blot analyses., Results: Our data showed that hDPSCs expressed the typical endothelial markers, which were up-regulated after endothelial induction, and were able to form tube-like structures. RPPA analyses revealed that these properties were modulated when a pulsatile unidirectional flow shear stress was applied to hDPSCs. Stem cells also revealed a downregulation of the immune-modulatory molecule PD-L1, in parallel with an up-regulation of the pro-inflammatory molecule NF-kB. Immune-modulatory properties of hDPSCs were also reduced after culture under flow-dependent shear stress and exposure to an inflammatory microenvironment. This evidence was strengthened by the detection of up-regulated levels of expression of pro-inflammatory cytokines in PBMCs., Conclusions: In conclusion, the application of a pulsatile unidirectional flow shear stress induced a modulation of immunomodulatory/inflammatory properties of dental pulp pericyte-like cells., (© 2023. The Author(s).)
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- 2023
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135. An arthroscopic repair technique for proximal anterior cruciate tears in children to restore active function and avoid growth disturbances.
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Turati M, Rigamonti L, Zanchi N, Piatti M, Gaddi D, Gorla M, Omeljaniuk RJ, Courvoisier A, and Bigoni M
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- Arthroscopy, Child, Follow-Up Studies, Humans, Knee Joint, Retrospective Studies, Treatment Outcome, Anterior Cruciate Ligament, Anterior Cruciate Ligament Injuries surgery
- Abstract
Purpose: The aim of this study was to assess midterm clinical outcomes in Tanner 1-2 patients with proximal anterior cruciate ligament (ACL) tears following arthroscopic-surgical repair using an absorbable or an all-suture anchor., Methods: Fourteen (9.2 ± 2.9 years-old) of 19 skeletally immature patients reached the 2 years of clinical follow-up. Physical examinations included the Lachman test, Pivot-shift test, One-leg Hop test, Pedi-IKDC as well as Lysholm and Tegner activity scores; knee stability was measured with a KT-1000 arthrometer. Overall re-rupture rates were also evaluated in all operated patients., Results: At 2 years post-surgery, the Lysholm score was 93.6 ± 4.3 points, and the Pedi-IKDC score was 95.7 ± 0.1. All patients returned to the same sport activity level as prior to ACL lesion within 8.5 ± 2.9 months, with one exception who reported a one-point reduction in their Tegner Activity score. No leg-length discrepancies or malalignments were observed. Four patients presented grade 1 Lachman scores, and of these, three presented grade 1 (glide) score at Pivot-shift; clinical stability tests were negative for all other patients. Anterior tibial shift showed a mean side-to-side difference of 2.2 mm (range 1-3 mm). The One-leg Hop test showed lower limb symmetry (99.9% ± 9.5) with the contralateral side. Overall, 4 out of 19 patients presented a re-rupture of the ACL with a median time between surgery and re-rupture of 3.9 years (range 1-7)., Conclusion: This surgical technique efficiently repairs proximal ACL tears, leading to a restoration of knee stability and a quick return to an active lifestyle, avoiding growth plate disruption., Level of Evidence: IV., (© 2020. The Author(s).)
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- 2021
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136. Push-pull unsymmetrical substitution in nickel(ii) complexes with tetradentate N 2 O 2 Schiff base ligands: synthesis, structures and linear-nonlinear optical studies.
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Rigamonti L, Forni A, Righetto S, and Pasini A
- Abstract
New push-pull (A-D) nickel(ii) compounds of general formula [Ni(5-A-5'-D-saltn)] (3a-3l) with unsymmetrically-substituted N
2 O2 tetradentate Schiff base ligands are reported here. The ligands 5-A-5'-D-saltn2- (H2 saltn = N,N'-bis(salicylidene)diaminopropane) possess differently-substituted salicylaldehyde (A/D sal) moieties condensed to 1,3-diaminopropane (tn), and carry either an electron acceptor (A = H, Br, or NO2 ) or donor (D = H, Me, or OMe) group in the para position with respect to the coordinated phenoxido oxygen atoms. These compounds could be obtained by template synthesis involving derivatives [Ni(G sal)2 (H2 O)2 ], 1a-e (G = NO2 , Br, H, Me and OMe, respectively) and [Ni(G L)2 ], 2a-d (G L- = (E)-2-((3-aminopropylimino)methyl)-4-G-phenolate, G = NO2 , Br, H and Me, respectively). Scrambling of the ligands and condensation to compounds 3 was suitably achieved by refluxing compounds 1 and 2 that carry the G groups suitable for the desired final A-D combination. Dinuclear intermediates [Ni2 (μ-G L)2 (G' sal)2 ] (4a,b,e,f,g) were also detected and isolated. The single-crystal X-ray diffraction structures of [Ni(5'-OMe-saltn)]·CHCl3 (3c·CHCl3 ), [Ni(5-Br-5'-OMe-saltn)]·EtOH (3g·EtOH) and [Ni(5-NO2 -saltn)] (3j) show different degrees of distortion around the central core, leading to saddle-like (3c), planar (3g) and step-like (3j) molecular conformations. DFT geometrical optimization of the compounds showed that, for isolated molecules, the saddle-like conformation is slightly more stable with respect to the other conformations. UV-visible absorption spectra showed structured absorption profiles at about 320-440 nm, whose intensity was amplified by the presence of the nitro group, and this was assigned to a convolution of one metal-to-ligand charge transfer and two intra-ligand charge transfer transitions by TDDFT computations. Surprisingly, UV-visible spectra of the derivatives with Br were comparable to the derivatives with Me, suggesting that in this case the behaviour of the halogen was as a weak electron donor group. The experimental investigation (through electric-field-induced second-harmonic and solvatochromic measurements) of the second-order NLO responses of compounds 3, in conjunction with the theoretical calculations, revealed that the observed NLO efficiency is determined by the combined effect of two almost orthogonal charge transfer directions within the molecules, one along the axis approximately bisecting the donor and the accepting moieties and the other along the A-D axis.- Published
- 2019
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137. A Pseudo-Octahedral Cobalt(II) Complex with Bispyrazolylpyridine Ligands Acting as a Zero-Field Single-Molecule Magnet with Easy Axis Anisotropy.
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Rigamonti L, Bridonneau N, Poneti G, Tesi L, Sorace L, Pinkowicz D, Jover J, Ruiz E, Sessoli R, and Cornia A
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The homoleptic mononuclear compound [Co(bpp-COOMe)
2 ](ClO4 )2 (1) (bpp-COOMe=methyl 2,6-di(pyrazol-1-yl)pyridine-4-carboxylate) crystallizes in the monoclinic C2/c space group, and the cobalt(II) ion possesses a pseudo-octahedral environment given by the two mer-coordinated tridentate ligands. Direct-current magnetic data, single-crystal torque magnetometry, and EPR measurements disclosed the easy-axis nature of this cobalt(II) complex, which shows single-molecule magnet behavior when a static field is applied in alternating-current susceptibility measurements. Diamagnetic dilution in the zinc(II) analogue [Zn(bpp-COOMe)2 ](ClO4 )2 (2) afforded the derivative [Zn0.95 Co0.05 (bpp-COOMe)2 ](ClO4 )2 (3), which exhibits slow relaxation of magnetization even in zero field thanks to the reduction of dipolar interactions. Theoretical calculations confirmed the overall electronic structure and the magnetic scenario of the compound as drawn by experimental data, thus confirming the spin-phonon Raman relaxation mechanism, and a direct quantum tunneling in the ground state as the most plausible relaxation pathway in zero field., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)- Published
- 2018
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138. Diamondoid Structure in a Metal-Organic Framework of Fe4 Single-Molecule Magnets.
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Rigamonti L, Cotton C, Nava A, Lang H, Rüffer T, Perfetti M, Sorace L, Barra AL, Lan Y, Wernsdorfer W, Sessoli R, and Cornia A
- Abstract
A 3D metal-organic framework (MOF) having single-molecule magnet (SMM) linkers was prepared in crystalline form by using a tetrairon(III) complex functionalised with two divergent pyridyl groups, namely [Fe4 (pPy)2 (dpm)6 ] (1; H3 pPy=2-(hydroxymethyl)-2-(pyridin-4-yl)propane-1,3-diol, Hdpm=dipivaloylmethane). Reaction of 1 with silver(I) perchlorate afforded {[Fe4 (pPy)2 (dpm)6 ]2 Ag}ClO4 (2), which crystallises in a cubic face-centred lattice and exhibits two interlocked diamondoid networks. In 2, the SMMs act as linear ditopic synthons, and silver(I) ions as tetrahedral nodes coordinated by four pyridyl nitrogen atoms. The magnetic properties of 1 (S=5 and D≈-0.4 cm(-1) in the ground spin state) are largely preserved in 2, which shows slow magnetic relaxation with an anisotropy barrier of Ueff /kB =11.46(10) K in zero field and 14.25(8) K in an applied field of 1 kOe. However, crystal symmetry triggers highly noncollinear magnetic anisotropy contributions oriented at 109.47° from each other along the threefold axes of AgN4 tetrahedra, a unique scenario fully confirmed by a single-crystal cantilever torque magnetometry investigation. Magnetisation curves down to 0.03 K demonstrated the occurrence of a wide hysteresis loop when the magnetic field was swept along one of the four Ag-N bonds. By symmetry, the crystalline compound can then be persistently magnetised parallel or antiparallel to the four main diagonals of the unit cell, although the crystals have no overall second-order anisotropy., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2016
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139. Experimental and Theoretical Studies on the Magnetic Anisotropy in Lanthanide(III)-Centered Fe3 Ln Propellers.
- Author
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Rigamonti L, Nava A, Boulon ME, Luzon J, Sessoli R, and Cornia A
- Abstract
Compounds [Fe3 Ln(tea)2 (dpm)6 ] (Fe3 Ln; Ln= Tb-Yb, H3 tea=triethanolamine, Hdpm=dipivaloylmethane) were synthesized as lanthanide(III)-centered variants of tetrairon(III) single-molecule magnets (Fe4 ) and isolated in crystalline form. Compounds with Ln=Tb-Tm are isomorphous and show crystallographic threefold symmetry. The coordination environment of the rare earth, given by two tea(3-) ligands, can be described as a bicapped distorted trigonal prism with D3 symmetry. Magnetic measurements showed the presence of weak ferromagnetic Fe⋅⋅⋅Ln interactions for derivatives with Tb, Dy, Ho, and Er, and of weak antiferromagnetic or negligible coupling in complexes with Tm and Yb. Alternating current susceptibility measurements showed simple paramagnetic behavior down to 1.8 K and for frequencies reaching 10000 Hz, despite the easy-axis magnetic anisotropy found in Fe3 Dy, Fe3 Er, and Fe3 Tm by single-crystal angle-resolved magnetometry. Relativistic quantum chemistry calculations were performed on Fe3 Ln (Ln=Tb-Tm): the ground J multiplet of Ln(3+) ion is split by the crystal field to give a ground singlet state for Tb and Tm, and a doublet for Dy, Ho, and Er with a large admixture of mJ states. Gyromagnetic factors result in no predominance of gz component along the threefold axis, with comparable gx and gy values in all compounds. It follows that the environment provided by the tea(3-) ligands, though uniaxial, is unsuitable to promote slow magnetic relaxation in Fe3 Ln species., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2015
- Full Text
- View/download PDF
140. Redox-Controlled Exchange Bias in a Supramolecular Chain of Fe4 Single-Molecule Magnets.
- Author
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Nava A, Rigamonti L, Zangrando E, Sessoli R, Wernsdorfer W, and Cornia A
- Abstract
Tetrairon(III) single-molecule magnets [Fe4(pPy)2(dpm)6] (1) (H3pPy=2-(hydroxymethyl)-2-(pyridin-4-yl)propane-1,3-diol, Hdpm=dipivaloylmethane) have been deliberately organized into supramolecular chains by reaction with Ru(II)Ru(II) or Ru(II)Ru(III) paddlewheel complexes. The products [Fe4(pPy)2(dpm)6][Ru2(OAc)4](BF4)x with x=0 (2 a) or x=1 (2 b) differ in the electron count on the paramagnetic diruthenium bridges and display hysteresis loops of substantially different shape. Owing to their large easy-plane anisotropy, the s=1 diruthenium(II,II) units in 2 a act as effective s(eff)=0 spins and lead to negligible intrachain communication. By contrast, the mixed-valent bridges (s=3/2, s(eff)=1/2) in 2 b introduce a significant exchange bias, with concomitant enhancement of the remnant magnetization. Our results suggest the possibility to use electron transfer to tune intermolecular communication in redox-responsive arrays of SMMs., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2015
- Full Text
- View/download PDF
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