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Developing high-performance anti-corrosion coating is an effective way of preventing metal surface from environmental corrosion. Polymethylhydrosiloxane (PMHS) precursor was utilized in combination with nano-zirconia (ZrO2) particles to prepare SiCxO-ZrO2 ceramic coating by means of high-temperature pyrolysis at 800 °C. A series of characterizations, including chemical structure, thermal stability, crystalline structure, microscopic morphology, and mechanical and electrochemical properties, were conducted to reveal the relation between the structure and the performance of the ceramic coatings. It was observed that the SiCxO-ZrO2 coating containing 20 wt% ZrO2 exhibited a hardness greater than 9H, impact resistance of 50 cm, water contact angle as high as 132°, and excellent corrosion resistance, which was attributed from the reparative effect of ZrO2 on ceramic coatings. This coating shows significant potential for use in storage tank anti-corrosion applications. [ABSTRACT FROM AUTHOR]

Employing the new nitronyl nitroxide biradical ligand biNIT-3Py-5-Ph (2-(5-phenyl-3-pyridyl)-bis(4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide)), a 16-spin Cu-radical complex, [Cu8(biNIT-3Py-5-Ph)4(hfac)16] 1, and three 2p-3d-4f chain complexes, {[Ln(hfac)3][Cu(hfac)2]2(biNIT-3Py-5-Ph)2}n (LnⅢ= Gd 2, Tb 3, Dy 4; hfac = hexafluoroacetylacetonate), have been prepared and characterized. X-ray crystallographic analysis revealed in all derivatives a common cyclic [Cu-biNIT]2 secondary building unit in which two bi-NIT-3Py-5-Ph biradical ligands and two CuII ions are associated via the pyridine N atoms and NO units. For complex 1, two such units assemble with four additional CuII ions to form a discrete complex involving 16 S = 1/2 spin centers. For complexes 2–4, the [Cu-biNIT]2 units are linked by LnIII ions via NO groups in a 1D coordination polymer. Magnetic studies show that the coordination of the aminoxyl groups with Cu or Ln ions results in behaviors combining ferromagnetic and antiferromagnetic interactions. No slow magnetic relaxation behavior was observed for Tb and Dy derivatives. [ABSTRACT FROM AUTHOR]

Dicyclopentyl substituted cucurbit[6]uril (CyP2Q[6]) is used to construct supramolecular self‐assembly with Ca and Er ions, respectively, and the obtained crystals are characterized by the X‐ray single crystal diffraction technique, with results showing that two Ca2+ form coordination bonds with two CyP2Q[6] carbonyl oxygen atoms and ten water molecules, respectively, while Er3+ first coordinates with eight water molecules and then forms hydrogen bonds through the coordinated water with the portal carbonyl oxygen on the CyP2Q[6], thus forming a 1D supramolecular chain, and a honeycomb‐like framework between two adjacent CyP2Q[6] through [ZnCl4]2–. [ABSTRACT FROM AUTHOR]

Herein, by using different size of organic molecules as cation templates, we prepared four new two‐dimensional (2D) lead halide perovskites, [PrPipz]PbBr4 (1), [DMEDA]PbBr4 (2), [TMEDA]0.5[DMA]PbCl4 (3) and [TMA]4Pb3Cl10 (4). Under the distinct structural directing effects of organic cations, compounds 1–4 present four different types of 2D inorganic layers. Remarkably, compounds 1, 3 and 4 exhibit broadband blue emissions, while compound 2 exhibits broadband yellow emission upon the excitation of UV light at room temperature. This work paves a way to modulate the crystal structure and photoluminescent property of low‐dimensional halide perovskite via structural modulation strategy from the molecular level. [ABSTRACT FROM AUTHOR]

An end-on azido-bridged dinuclear copper(II) complex, [Cu2L2(μ1,1-N3)2], where L is the deprotonated form of N-(2-hydroxy-4-methoxybenzylidene)picolinamide (HL), has been prepared by the reaction of 5-methoxy-2-[(pyridin-2-ylmethylimino)methyl]phenol (HL′) with copper bromide and sodium azide in methanol. The structure of the complex was characterized by elemental analysis, IR and UV–vis spectra, and single crystal X-ray diffraction. The complex possesses crystallographic inversion symmetry, with the two Cu ions (3.36 Å) bridged by two end-on azido bridges. Each Cu ion is in a square pyramidal coordination. The original ligand HL′ was unexpectedly oxidized to HL under mild conditions during preparation of the complex. The complex has excellent urease inhibitory activity. [ABSTRACT FROM AUTHOR]

It remains significant to explore new types of hybrid lead halides to realize the diversifications of structural and luminescence properties due to the excellent optoelectronic performances of perovskites. Herein, by choosing various organic molecules as cationic templates, we constructed a series of new one-dimensional (1D) lead halide perovskites, namely, [DMEDA]Pb2Br6·H2O (1), [ATMPD]Pb2Br6·H2O (2) and [TMPrDA]2Pb3X10 (3: X = Br; 4: X = Cl). The crystal structures of compounds 1–4 contain 1D [Pb2Br6]2− and [Pb3X10]4− chains based on [Pb4X16] tetramer clusters as basic building units, respectively. Remarkably, compound 2 displays broadband yellow light emissions spanning the entire visible spectral range and centered at 534 nm, which can be ascribed to self-trapped excitons based on systematic characterization including time-resolved PL emission and theoretical studies. This work provides a series of new low-dimensional hybrid lead halides as prototypes to enrich the halide chemistry including crystal engineering and optoelectronic performance. [ABSTRACT FROM AUTHOR]

Abstract: A recent trend in the development of new optimized materials makes use of crystalline domains having nanometer sizes for which characterization methods at the atomic scale are mandatory. Amongst them is pair‐distribution function analysis (PDF‐analysis), a diffraction technique that has already shown that a short‐range or “local” atomic structure of a given domain, having a lower symmetry than the average long‐range structure, often exists in many compounds having valuable properties for industrial applications, such as pyrochlores, spinels, and doped ceria among others. However, the manner by which these domains are arranged to produce the average long‐range structure is still an open question. Herein, the first structural model that accounts for both the local structure (inside a given domain) and the long‐range structure (averaged over all domains) that is observed in the PDF of uranium dioxide is presented. The structural model describes domain walls in such a way as to preserve the uranium coordination polyhedron and to obey the needed symmetry rules. The proper description of domain walls is an important step in the understanding and the modelling of nanostructured materials. [ABSTRACT FROM AUTHOR]

Abstract: A recent trend in the development of new optimized materials makes use of crystalline domains having nanometer sizes for which characterization methods at the atomic scale are mandatory. Amongst them is pair‐distribution function analysis (PDF‐analysis), a diffraction technique that has already shown that a short‐range or “local” atomic structure of a given domain, having a lower symmetry than the average long‐range structure, often exists in many compounds having valuable properties for industrial applications, such as pyrochlores, spinels, and doped ceria among others. However, the manner by which these domains are arranged to produce the average long‐range structure is still an open question. Herein, the first structural model that accounts for both the local structure (inside a given domain) and the long‐range structure (averaged over all domains) that is observed in the PDF of uranium dioxide is presented. The structural model describes domain walls in such a way as to preserve the uranium coordination polyhedron and to obey the needed symmetry rules. The proper description of domain walls is an important step in the understanding and the modelling of nanostructured materials. [ABSTRACT FROM AUTHOR]

The present work verifies the existence of chemical short-range orders (CSROs) in high-entropy alloys (HEAs) using a cluster-plus-glue-atom model. Two HEAs with a composition of Al 2 M 14 (M = Ni 4 Co 4 Fe 3 Cr 3 or Ni 1 Co 1 Fe 2 Cr 1 ) are designed, which is derived from the cluster model of [Al-M 12 ](M 2 Al 1 ) in face-centered-cubic structure or [Al-M 14 ]Al 1 in body-centered-cubic structure. It is found that the calculated pair-distribution functions (PDFs) at short inter-atomic distances by these cluster models can describe the neutron PDFs better than the ones by the average crystal structures. It is due to the different CSROs characterized by cluster units that induce the structural transition of HEAs. [ABSTRACT FROM AUTHOR]

Two manganese(ii) homometallic coordination polymers of compositions [Mn(CN)2(pz)]n (1) and {[Mn4(CN)8(bpy)3(EtOH)1.14(H2O)0.86]·bpy}n (2) have been synthesized in an inert atmosphere. In these compounds, metal cyanide 2D layers are linked into 3D networks by pillar ligands. Antiferromagnetic coupling occurs between Mn(ii) ions and the antiferromagnetic ordering in these compounds is observed with Neel temperatures (TN) of 20.0 K in complex 1 and 8.0 K in complex 2. [ABSTRACT FROM AUTHOR]

A trinuclear chromium(III) complex, [Cr3O(HCO2)6(CH3OH)3]NO3·H2O·CH3OH ( 1), is synthesized and structurally characterized by single-crystal X-ray diffraction. Three chromium(III) ions are bridged by one oxygen atom in the center, forming a triangular structure. The HCOO − anion acts as bidentate ligand and bridges couples of Cr(III) ions. Magnetic susceptibility measurement indicates that a strong antiferromagnetic interaction is operative between chromium(III) ions, and the S = 1/2 ground state reveals normal spin frustration behavior. [ABSTRACT FROM AUTHOR]

In recent years, organic-inorganic hybrid metal halides were given tremendous attention in solid-state lighting fields owing to diversified structures and excellent photoluminescence performances. In this work, we report three isostructural organic–inorganic hybrid lead silver bimetallic halides of [Pb(PDA) 2 ] 2 Ag 2 X 6 (X ​= ​Cl (1), Br (2), I (3)) by choosing organic amine of 1,2-propanediamine (PDA) as ligand. In their crystal structure, dimeric [Ag 2 X 6 ]4- anions are bridged by [Pb(PDA) 2 ]2+ complex cations via weak Pb-X bonds to form three-dimensional [Pb(PDA) 2 ] 2 Ag 2 X 6 network. Despite the crystal structures of iodide phase has been reported, the luminescence properties of this system remain not yet characterized. Excitedly, under UV light excitation, compounds 2 displays broad-band yellow light emissions with highest photoluminescence quantum yield (PLQY) of 2.26% among three samples. By coating sample of compound 2 on a blue chip, a white light emitting diode (LED) can be easily obtained. This work provides ideas for studying the structure-property relationship of organic-inorganic hybrid bimetallic halides. Three isostructural lead silver bimetallic halides of [Pb(PDA) 2 ] 2 Ag 2 X 6 (X ​= ​Cl, Br, I) display broadband yellow emissions. [Display omitted] • Three isostructural Pb–Ag bimetallic halides of [Pb(PDA) 2 ] 2 Ag 2 X 6 (X ​= ​Cl, Br, I). • Under UV light excitation, three compounds display yellow light emissions. • Compound 2 photoluminescence quantum yield (PLQY) of 2.26%. • As suitable down-conversion phosphors to fabricate white light emitting diode. [ABSTRACT FROM AUTHOR]

Two heterospin complexes [Cu(NIT3Py)(cda)H2O] ·H2O ( 1) and [Cu(NIT2Py)(cda)H2O] ·H2O ·CH3OH ( 2) with CuII ions and pyridyl-substituted nitronyl nitroxide radicals (NIT xPy = 2-( x′-pyridyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide, x = 3, 2; H2cda = 4-hydroxy-pyridine-2,6-dicarboxylic acid) were synthesized and characterized structurally and magnetically. The single crystal structures show that the two complexes are both two-spin complexes, in which the different radicals make the two complexes have different hydrogen bonding interactions to form 2D and 1D supramolecular network for complexes 1 and 2, respectively. The magnetic measurements indicate that complexes 1 and 2 both exhibit antiferromagnetic interactions between CuII and radicals. [ABSTRACT FROM AUTHOR]

Two new lanthanide–radical complexes, [Tb(hfac)3(EtVNIT)2] (1) and [Dy(hfac)3(EtVNIT)2] (2) (EtVNIT = 2-(4′-ethoxy-3′-methoxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, hfac = 1,1,1,5,5,5-hexafluoroacetylacetonate), were synthesized; both display radical–Ln(III)–radical (Ln=Tb (1), Dy (2)) tri-spin structures. Magnetic studies reveal that interactions between the lanthanide ions and radicals are ferromagnetic. [ABSTRACT FROM PUBLISHER]

A new complex [Mn(hfac)2NIT(Ph-m-OPh)] has been synthesized and structurally characterized by X-ray diffraction. It crystallizes in the monoclinic space group P2(1)/c. The structure consists of a 1-D chain with Mn(II) bridged by NIT(Ph-m-OPh). The manganese(II) is in a distorted octahedral environment formed by one oxygen from NIT(Ph-m-OPh) and three atoms from hexafluoro acetylacetone (hfac) in the equatorial plane and two oxygens from hfac and the other NIT(Ph-m-OPh) in the axial position. The units of [Mn(hfac)2NIT(Ph-m-OPh)] are connected as a 1-D chain by Mn(II) and oxygen of N–O in bridging NIT(Ph-m-OPh) along the b-axis. The 2-D layer in the ab plane is formed via hydrogen interactions to connect neighboring chains. The complex exhibits intramolecular antiferromagnetic interactions between Mn(II) and NIT(Ph-m-OPh). [ABSTRACT FROM AUTHOR]

A supramolecular assembly of [p-MePyNN]2[Au(CN)2]2 (1) (p-MePyNN+ = 2-(4-N-methylpyridinium)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazo-1-oxyl-3-oxide radical cation) has been synthesized from the combination of p-N-methylpyridinium nitronyl nitroxide radical cations and [Au(CN)2]- anions, and characterized structurally as well as magnetically. The compound crystallizes in the orthorhombic, space group P212121, with two independent p-MePyNN+ cations separated from each other by the dimer [image omitted]. The magnetic study shows that the larger steric hindrance of [Au(CN)2]- anion influences the magnetic interactions between the radical cations, with very weak antiferromagnetic interactions. [ABSTRACT FROM AUTHOR]

Abstract: A transition metal-radical heterospin complex [Ni(salox)2(IM4Py)2] (1) (salox=salicylaldoxime, IM4Py=2-(4′-pyridinyl)-4,4,5,5-tetramethylimidazoline-l-oxyl) (1) has been synthesized based on the substitution reaction of Ni(salox)2(py)2 and IM4Py. Compound 1 exhibits a chain structure created by the intermolecular hydrogen bonds. Magnetic measurements show intermolecular antiferromagnetic interactions in 1. [Copyright &y& Elsevier]

Abstract: A novel copper(II)-radical complex [Cu(NITmPy)(PDA)(H2O)]·(H2O) (1) (NITmPy=2-(3′-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, H2PDA=2,6-pyridinedicarboxylic acid) has been synthesized and structurally characterized by X-ray diffraction methods. It crystallizes in the triclinic space group . The Cu(II) ion exists in a distorted square pyramid environment. The molecules of [Cu(NITmPy)(PDA)(H2O)]·(H2O) are connected as a two-dimensional structure by the intermolecular hydrogen bonds. Magnetic measurements show intramolecular ferromagnetic interactions between NITmPy and Cu(II) ion and intermolecular antiferromagnetic interactions in 1. [Copyright &y& Elsevier]

Abstract: A novel complex, [Gd(hfac)3(NIT-5-Br-3py)]2 (hfac=hexafluoroacetylacetonat, NIT-5-Br-3py=2-(4,4,5,5-tetramethyl-3-oxylimidazoline-1-oxide)-5-bromo-3-pyridine) has been synthesized and characterized structurally and magnetically, in which a NIT-5-Br-3py molecular acts as a bridge ligand linking two Gd(III) ions through the oxygen atom of the N–O group and nitrogen atom from the pyridine ring to form a four-spin system. The fitting result of the magnetic susceptibility shows two different magnetic interactions between Gd(III) ion and NIT-5-Br-3py in one complex: a weak ferromagnetic interaction (J 1 =+2.60cm−1) through the N–O group, and a much weaker antiferromagnetic (J 2 =−0.24cm−1) interaction through pyridine ring. [Copyright &y& Elsevier]

Rare earth elements are recently attracting more and more interests due to their dramatic effect as alloying elements. However the study regarding the phase equilibria between rare earth elements are still rare. The thermodynamically stable phases within the ∼50 at.%Y region have been investigated for the La-Y binary system using differential scanning calorimetry, scanning electron microscopy and transmission electron microscopy in the present work. The samarium-type δ-LaY has been found to be unstable while a pure Y phase with fcc crystal structure has been observed. A new invariant reaction has been determined to be bcc-(La,Y) + fcc-Y → dhcp-(La,Y) at 717 ± 3 °C. [ABSTRACT FROM AUTHOR]

Abstract: Five novel Ln(III) complexes based on a new nitronyl nitroxide radical have been synthesized, characterized structurally and magnetically: [Ln(hfac)3(NITPh-3-Br-4-OMe)2] (Ln(III)=Eu(1), Gd(2), Tb(3), Dy(4), Ho(5); hfac=hexafluoroacetylacetonate; and NITPh-3-Br-4-OMe=2-3′-Br-4′-methoxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide). The single-crystal structures analyses show that these complexes have similar mononuclear tri-spin structures, in which central Ln(III) ions are all eight coordinated by three hfac molecules and two NITPh-3-Br-4-OMe radicals. The variable-temperature magnetic susceptibility studies reveal the antiferromagnetic interactions between the paramagnetic ions (Ln(III) and radicals) in complexes 1, 2, 3 and 5 and ferromagnetic interaction in complex 4. The luminescence characterizations of complexes Eu(1), Tb(3) and Dy(4) are also studied in this paper. [Copyright &y& Elsevier]

Abstract: Two lanthanide-radical complexes [Tb(hfac)3(IM-2py)] (1) and [Tb(hfac)3(IM-2thz)] (2) (hfac=hexafluoroacetylacetonate; IM-2py=2-(2′-pyridyl)-4,4,5,5-tetramethyl- imidazoline-1-oxyl; IM-2thz=2-(2′-thiazolyl)-4,4,5,5-tetramethylimidazoline-1-oxyl) have been synthesized. Single crystal X-ray diffraction analysis reveals that complexes 1 and 2 are mononuclear complexes in which the IM-2py/IM-2thz radical is coordinated to the Tb(III) ion in a chelating way. The similar magnetic behavior is observed for two compounds through direct current magnetic measurements, implying antiferromagnetic coupling between Tb(III) and imino nitroxide radical. Alternating current magnetic susceptibility studies show that both complexes exhibit frequency-dependent out-of-phase signals indicative of a slow relaxation of magnetization. [Copyright &y& Elsevier]

• Supramolecular self-assembly between cyclopentanocucurbit[6]uril and 1 H -benzotriazole. • Supramolecular framework of BTA@CyP 6 Q[6] has obvious pore structure. • CyP 6 Q[6] combines with TBA through an enthalpy driven process to enhance the thermal stability of TBA. In this paper, the host-guest supramolecular interactions between cyclopentanocucurbit[6]uril with 1 H -benzotriazole (BTA) have been investigated using 1H NMR spectroscopy, isothermal titration calorimetry (ITC), HPLC-QTOF mass spectrometry, IR spectroscopy, thermogravimetric analysis and single crystal X-ray diffraction. The results show that there is a 1:1 mode of inclusion in BTA@CyP 6 Q[6], which forms a supramolecular framework through hydrogen bonds and dipole interactions. In addition, the benzene ring of the BTA molecule entered the cavity of CyP 6 Q[6], while the triazole part resided at the port of the CyP 6 Q[6]. According to the ITC data, the complexation process for BTA with CyP 6 Q[6] is mainly driven by enthalpy. [Display omitted] [ABSTRACT FROM AUTHOR]

The diffusion reaction of 1,4-bis(1,2,4-triazol-1-yl)butane (btb) with Co(II)/Ni(II) ions as well as counter anions (PF 6 − ) yielded two new coordination polymers, [Co 1.5 (btb) 4.5 ](PF 6 ) 3 ( 1 ) and [Ni 2 (btb) 6 ](PF 6 ) 4 ( 2 ). Both complexes have 3D uninodal 6-connected (4 12 ,6 3 ) net topology, forming triple interpenetrating structure. The distance between adjacent metal ions via btb bridging ligand is in the range of 13.930–14.181 Å and 13.982–14.086 Å, respectively. The magnetic behaviors of complexes 1 and 2 have been analyzed by one-ion approximation with spin–orbit coupling and zero-field splitting, respectively. [ABSTRACT FROM AUTHOR]

A series of bis(triazole)-Fe(II) coordination polymers, {[Fe(NCS) 2 (btm) 2 ]·H 2 O} n ( 1 ), {[Fe(bte) 2 (NCS) 2 ][Fe(bte)(H 2 O) 2 (NCS) 2 ]} n ( 2 ), [Fe(NCS) 2 (btp) 2 ] n ( 3 ), {[Fe(NCS) 2 (btb) 2 ] a [Fe(NCS) 2 (btb) 2 ] b } n ( 4 ) and [Fe(NCS) 2 (bth) 2 ] n ( 5 ) (btm = bis-(1,2,4-triazol-1-yl)methane, bte = 1,2-bis-(1,2,4-triazol-1-yl)ethane, btp = 1,3-bis-(1,2,4-triazol-1-yl)propane, btb = 1,4-bis(1,2,4-triazol-1-yl)butane, bth = 1,6-bis(1,2,4-triazol-1-yl)hexane), have been synthesized and structural characterized by X-ray single-crystal diffraction. Compounds 1 – 3 are 1D chains, complex 4 is a mixture of 2D networks and 1D chains, while complex 5 has 2-fold interpenetrated frameworks of [Fe(NCS) 2 (bth) 2 ] n 2D planes. The iron(II) ions in complexes 1 – 5 all remain in the high spin state down to 2 K and the experimental data were fitted by using the single ion approximation for Fe(II) ion with zero-field splitting of ground-state quintet. [ABSTRACT FROM AUTHOR]

Two Mn(II) complexes based on two nitronyl nitroxide radicals with different substituent R groups have been synthesized, and characterized structurally and magnetically: [[Mn(hfac) 2 ] 3 (NITPyOMe) 2 ] ( 1 ) (hfac = hexafluoroacetylacetonate, NITPyOMe = 2-(5′-(2″-methoxy)pyridyl)-4,4,5,5-tetramethylimidazozoline-1-oxyl-3-oxide) and [[Mn(hfac) 2 ] 3 (NITPhOEt) 2 ] ( 2 ) (NITPhOEt = 4′-ethoxyphenyl-4,4,5,5- tetra-methylimidazoline-1-oxyl-3-oxide). The X-ray crystal structure analyses show that modifying the substituent R groups with a donor N atom helps to get the one-dimensional Mn(hfac) 2 -bridged [Rad–Mn(hfac) 2 ] 2 chain complex 1 , while the large steric hindrance of the NITPhOEt radical induces complex 2 to be a mononuclear tri-spin compound, in which the central Mn(II) ion is coordinated by two hfac and two NITPhOEt radicals. Variable temperature magnetic susceptibility studies reveal that there are antiferromagnetic interactions between the Mn(II) ions and the radical through the N–O group in both of the two complexes. [ABSTRACT FROM AUTHOR]

By utilizing 4-amino-3,5-dimethyl-1,2,4-triazole as ligand, two new compounds, [Cu 3 (N 3 ) 6 (L) 4 ] ( 1 ) and {[Cu 3 (NO 3 ) 5 (OH)(L) 3 ]·0.5H 2 O} n ( 2 ) (L = 4-amino-3,5-dimethyl-1,2,4-triazole), have been synthesized and characterized by single-crystal X-ray diffraction, IR spectroscopy, UV–Vis spectra and magnetic measurements. Compound 1 is a trinuclear Cu(II) complex, containing four L ligands and six N 3 − anions. In compound 2 , a one-dimensional chain structure was formed between the trinuclear Cu(II) units connected to each other by NO 3 − anions. The magnetic analysis indicates a middle strong antiferromagnetic exchange is propagated by 1,2,4-triazole bridging ligand. [ABSTRACT FROM AUTHOR]

Abstract: Four new copper(II) complexes containing different nitronyl nitroxide radicals have been synthesized, characterized structurally and magnetically: [(Cu(hfac)2)3(NITPh-3-Br-4-OMe)2] (1), [(Cu(hfac)2)3(NITPyOMe)2] (2), [Cu(hfac)2(2-QNNN)] (3) and [Cu(hfac)2(NITmNO2)2] (4) (hfac=hexafluoro-acetylacetonate; and NITPh-3-Br-4-OMe=2-3′-Br-4′-methoxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, NITPyOMe=2-4′-methoxy-3′-pyridyl-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide, 2-QNNN=2-2′-quinolyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, NITmNO2 =2-(3-nitrophenyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide). The X-ray crystal structure analyses show that complexes 1 and 2 have similar centrosymmetric five-spin structures built by three Cu(hfac)2 units bridged by two nitroxide ligands through their NO groups. While complex 3 consists of isolated molecule where the nitronyl nitroxide radical acts as chelating ligand towards copper(II), and complex 4 is a rare mononuclear tri-spin compound, in which central Cu(II) ion is coordinated by two hfac and two NITmNO2 radicals. The variable-temperature magnetic susceptibility studies reveal strong antiferromagnetic interactions between Cu(II) ions and radicals in complexes 1–2, practically diamagnetic in complex 3 and weak ferromagnetic interaction in complex 4. [Copyright &y& Elsevier]

Two new complexes, [MnIIILDyIII(hfac)2(CF3COO)(H2O)][DyIII(hfac)3(CF3COO)(H2O)]·2CHCl3 (1) and [MnIIIL(H2O)][TbIII(hfac)4]·CHCl3 (2) [L= N,N'-ethylene-bis(3-methoxy-salicylideneiminate), hfac=hexafluoroacetylacetone] were synthesized and structural characterized by X-ray single-crystal diffraction. The magnetic analysis was carried out by using the Hamiltonian of Ĥ = ΔĴz 2 for lanthanide ions and Ĥ = DŜ z 2 for Mn(III) ion, and the best fitting gives D =±2.98cm−1, Δ =−0.0014cm−1, zJ′=−0.017cm−1, g Dy =1.37, g Mn =2.02 for complex 1 and D =±0.23cm−1, Δ =0.0034cm−1, g Tb =1.52, g Mn =1.99 for complex 2. [ABSTRACT FROM AUTHOR]

Abstract: Two one-dimensional nitronyl nitroxide–lanthanide complexes [Ln(hfac)3(NITMe)] n (Ln(III)=Y (1), Dy(2), hfac=hexafluoroacetylacetonate; NITMe=2,4,4,5,5-pentamethylimidazolyl-1-oxyl-3-oxide) have been successfully prepared and characterized. Single crystal X-ray crystallographic analysis reveals that complexes 1 and 2 show similar linear chain structures composed of Ln(hfac)3 units bridged by NITMe radicals through their NO groups. Variable-temperature magnetic susceptibilities of Y complex show that there exists weak antiferromagnetic coupling between the radical ligands through the diamagnetic Y(III) ions. Alternating current (ac) susceptibilities of Dy complex reveal frequency dependent out-of-phase signals, indicating that it behaves as single-chain magnet. [Copyright &y& Elsevier]

Abstract: Three heterospin complexes [M(NIT4Py)2(cda)H2O] (M=Cu(II) (1), Ni(II) (2), Co(II) (3)) with various paramagnetic 3d metal ions and pyridyl-substituted nitronyl nitroxide radical (NIT4Py=2-(4′-pyridyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide, H2cda=4-hydroxy-pyridine-2,6-dicarboxylic acid) have been synthesized, characterized structurally and magnetically. The single crystal structures show that complexes 1–3 are isomorphic, and have 2D supramolecular network consisting of [M(NIT4Py)2(cda)H2O] with three paramagnetic centers. The magnetic measurements indicated that complexes 1–3 exhibit all antiferromagnetic interactions between M(II) and radicals with J Cu–rad =−7.30cm−1, J Ni–rad =−3.58cm−1 and J Co–rad =−1.85cm−1, respectively. Their magnetic behaviors were interpreted in terms of the spin polarization mechanism of the π-electrons of NIT4Py and the orthogonality of 3d magnetic orbital of M(II) ion and the 2pπ orbital on the pyridine rings of NIT4Py. [Copyright &y& Elsevier]

Abstract: Three new lanthanide complexes based on a novel nitronyl nitroxide radical [Ln(hfac)3(NITPhiPr)2] (Ln=Gd(1), Tb(2), Dy(3); hfac=hexafluoroacetylacetonate, NITPhiPr=4′-isopropyl-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) have been successfully synthesized, characterized structurally and magnetically, which all display radical-Ln(III)-radical tri-spin structures. The magnetic studies reveal the ferromagnetic interactions between the Gd(III) ion and radicals and the antiferromagnetic interaction between two radicals in the complex 1. And both Ln(III)–radical ferromagnetic interactions exist in complexes 2 and 3. [Copyright &y& Elsevier]

Abstract: Three new lanthanide-radical complexes containing the same radical ligand were successfully synthesized, which all display radical-Ln(III)-radical (Ln=Pr (1), Gd (2), Ho(3)) tri-spin structures. The magnetic studies revealed that, for complex 2, the interactions between the Gd(III) ion and radical are ferromagnetic, while the interaction between two radicals is antiferromagnetic. In complexes 1 and 3, antiferromagnetic couplings exist between the lanthanide ions and radicals. [Copyright &y& Elsevier]

Abstract: One unique radical-bridged Mn(II) cluster [Mn4(hfac)6(NIToBA)2(HIMoBAH)(H2O)3] (1) (hfac=hexafluoroacetylacetonate, NIToBAH=2-(2-carboxyphenyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazol-1-oxyl-3-oxide, HIMoBAH=2-(2-carboxyphenyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazol-1-hydroxy) has been synthesized and structurally and magnetically characterized. The core of complex 1 features four Mn(II) ions bridged by three carboxyl groups and two nitroxide groups to form a crown-like ring structure. This complex exhibits strong antiferromagnetic interaction because the NO groups are directly coordinated to the metal ions. [Copyright &y& Elsevier]

By using in situ N-alkylating [(Me) 2 -2,2-bipy]2+ organic cation as structural-directing agent (SDA), two new types of organic-inorganic hybrid cuprous halides, namely, [(Me) 2 -2,2-bipy]Cu 3 I 5 (1) and [(Me) 2 -bipy)] 2 Cu 7 Br 9 I 2 (2) , have been solvothermally synthesized and structurally characterized. The compound 1 crystallizes in the monoclinic space group P 2 1 / n (No. 147) and features one-dimensional (1D) anionic [Cu 3 I 5 2- chains separated by [(Me) 2 -2,2-bipy]2+ cations. The structure of compound 2 contains a 1D [Cu 7 Br 9 I 2 2- anionic chain, which belongs to the first hybrid cuprous halide with mixed halogen elements. The UV–vis absorption optical measurement reveals that the compounds possesses narrow band gaps of 1.95–2.14 ​eV, which leads to stable photocatalytic degradation activity over organic pollutant under visible light irradiation. The possible photocatalytic mechanism and reason of photochemical stability is also proposed based on experimental results and electronic band structural calculation. By using photosensitivity conjugated organic cations as structural template, we prepared two types of cuprous halides, namely as, [(Me) 2 -2,2-bipy]Cu 3 I 5 and [(Me) 2 -bipy)] 2 Cu 7 Br 9 I 2 , with one-dimensional anionic [Cu 3 I 5 2- and [Cu 7 Br 9 I 2 2- anionic chains charge balanced by [(Me) 2 -2,2-bipy]2+ cations. The photosensitization of conjugated organic cations leads to narrow band gaps of 1.95 eV–2.13 ​eV, which result in stable photocatalytic degradation activity over organic pollutant under visible light irradiation. Image 1 • Two new types of one-dimensional hybrid cuprous halides were prepared and characterized. • The [(Me) 2 -2,2-bipy]Cu 3 I 5 and [(Me) 2 -bipy)] 2 Cu 7 Br 9 I 2 have narrow band gaps of 1.95 eV–2.13 ​eV. • The cuprous halides result in stable photocatalytic properties under visible light irradiation. [ABSTRACT FROM AUTHOR]