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Stable aqueous dispersions of spin-crossover (SCO) doped [FeII(Htrz)2(trz)](BF4) nanoparticles (NPs) were prepared by using water-soluble polyvinylpyrrolidone (PVP) as protecting polymer. The metal or ligand substitution percentage regulated the ultra-small size and morphology of the NPs. At the same time, the colloidal dispersions showed a complete conversion of the LS state to the HS state of the FeII ion. [ABSTRACT FROM AUTHOR]

Surface-Enhanced Raman Spectroscopy (SERS) is a powerful, non-destructive technique for enhancing molecular spectra, first discovered in 1974. This study investigates the enhancement of Raman signals from single- and few-layer molybdenum disulfide (MoS2) when interacting with silver nanoparticles. We synthesized a MoS2 membrane primarily consisting of monolayers and bilayers through a wet chemical vapor deposition method using metal salts. The silver nanoparticles were either directly grown on the MoS2 membrane or placed beneath it. Raman measurements revealed a significant increase in signal intensity from the MoS2 membrane on the silver nanoparticles, attributed to localized surface plasmon resonances that facilitate SERS. Our results indicate that dichalcogenide/plasmonic systems have promising applications in the semiconductor industry. [ABSTRACT FROM AUTHOR]

A facile experimental protocol for the synthesis of poly(ethylene glycol)-modified (PEGylated) gold nanorods (AuNRs@PEG) is presented as well as an effective drug loading procedure using the non-steroidal anti-inflammatory drug (NSAID) naproxen (NAP). The interaction of AuNRs@PEG and drug-loaded AuNRs (AuNRs@PEG@NAP) with calf-thymus DNA was studied at a diverse temperature revealing different interaction modes; AuNRs@PEG may interact via groove-binding and AuNRs@PEG@NAP may intercalate to DNA-bases. The cleavage activity of the gold nanoparticles for supercoiled circular pBR322 plasmid DNA was studied by gel electrophoresis while their affinity for human and bovine serum albumins was also evaluated. Drug-release studies revealed a pH-sensitive behavior with a release up to a maximum of 24% and 33% NAP within the first 180 min at pH = 4.2 and 6.8, respectively. The cytotoxicity of AuNRs@PEG and AuNRs@PEG@NAP was evaluated against MCF-7 and MDA-MB-231 breast cancer cell lines. The development of AuNRs as an efficient non-steroidal anti-inflammatory drugs (NSAIDs) delivery system for chemotherapy is still in its infancy. The present work can shed light and inspire other research groups to work in this direction. [ABSTRACT FROM AUTHOR]

The synthesis, crystal structure and magnetic properties of two trinuclear oxo-centered carboxylate complexes, [[Cr.sub.3]([[mu].sub.3]-O)[([[mu].sub.6]-PhCOO).sub.6][([H.sub.2]O).sub.3]]N[O.sub.3].4[H.sub.2]O.2C[H.sub.3]OH (complex 1) and [[Cr.sub.3]([[mu].sub.3]-O)[([[mu].sub.2]-PhCOO).sub.2][([[mu].sub.2]-OC[H.sub.2]C[H.sub.3]).sub.2][(bpy).sub.2][(NCS).sub.3]] (complex 2), are described. The antisymmetric exchange interaction has played a major role in the magnetic behavior of the complex 1 and unusual skeleton of the [[Cr.sub.3]O] core is most important feature of complex 2.

The reaction of Ln([N[O.sub.3]).sub.3) with [K.sub.3][Cr[CN.su.6)] and 2,2-bipyridine (bpy) in a water/ethanol solution is found to lead to two families of complexes. The magnetic results obtained in the full lanthanide series using {[Fe[CN.sub.6]}.sup.3-] and bpy as the blocking ligand are presented.

Research delineates the use of 1,10-phenanthroline in Fe(sup)III carboxylate reactions leading to the production of three new tetranuclear iron(III)/phenanthroline complexes. The core structure of two of the title complexes show the tetranuclear cluster arranged in a 'butterfly' fashion. All three exhibit magnetic properties.

Results show that a cobalt(II)--semiquinonato adduct is detected in the range 4-300 K in the antiferromagnetic coupling between the high spin cobalt(II) ion and the radical semiquinonato ligand complex.

Copper complexes with commercial oxin herbicides MCPA, 2,4-D and 2,4,5-T in the presence of nitrogen donor heterocyclic ligand, phenanthroline or 2,2'-bipyridylamine are synthesized and characterized. The available evidence supports a dimeric structure for the 2,4-D complex in the presence of bipyam while phen leads to monomeric forms and the EPR spectrum of the dimer at 4 K exhibits an axial signal corresponding to almost isolated S = 1/2 magnetic ions.

Three dimensional (3D) polymeric complex [Cu(btaO)(sub 2)(MeOH)](sub n), where btaO(super -) is the anion of 1-hydroxybenzotriazole, display interesting structural and magnetic characteristics. The magnetic study of [Cu(btaO)(sub 2)(MeOH)](sub n) reveals the presence of long-range ferromagnetic interactions with two critical transitions at 6.4 and 4.4 K.

The 1 : 2 reaction between Dy(O2CMe)3·4H2O and 1-acetyl-2-napthol (LH) in MeOH has provided access to the complex [Dy2L6(MeOH)]·MeOH (1·MeOH) in a good yield. The structures of the isomorphous complex 1·MeOH and its doped diamagnetic yttrium analogue [Dy0.14Y1.86L6(MeOH)]·MeOH (Dy@Y2) have been determined by single-crystal X-ray crystallography and characterized based on elemental analyses, IR spectra, and powder X-ray patterns. Combined dc and ac magnetic susceptibility and the magnetization data for 1 suggest that this complex shows slow magnetic relaxation. Under a 0 Oe dc field, a single relaxation mechanism is seen while two magnetization relaxation processes are evident under a 1500 G external magnetic field. The fit to the Arrhenius law has been performed using the 1.8–10 K ac data, affording an effective barrier for the magnetization reversal of 13 K and 7 K under the external dc field. Theoretical studies have been performed using ab initio and density functional methodologies to understand the electronic structure and the magnetic relaxation dynamics resulting from the single DyIII ion as well as from the dinuclear exchange-coupled states. Rich powder EPR spectra at the X-band and Q-band were obtained from Dy@Y2, as well as from the 1·MeOH dimer, while simulation studies revealed the ferromagnetic nature of the interaction between the DyIII ions in accordance with theoretical studies. [ABSTRACT FROM AUTHOR]