Spin Crossover and Thermochromism in Iron(II) Complexes with 2,6-Bis(1-imidazol-2-yl)-4-methoxypyridine.

New iron(II) complexes with 2,6-bis(1-imidazol-2-yl)-4-methoxypyridine () of the composition [FeL]A∙mHO (A = SO, n = 1, m = 2 (); A = ReO, n = 2, m = 1 (); A = Br, n = 2, m = 2 ()) have been synthesized and investigated. To determine the coordination ability of the ligand, a single crystal of a copper(II) complex of the composition [CuLCl] () was obtained and studied by X-ray technique. Compounds - were studied using methods of X-ray phase analysis, electron (diffuse reflection spectra), infrared and Mössbauer spectroscopy, static magnetic susceptibility.

The Charge Distribution, Seebeck Coefficient, and Carrier Concentration of CuCrLnS (Ln = Dy-Lu).

The atom oxidation states were determined using the binding energies of the core S2p-, Cu2p-, Cr2p-, and Ln3d-levels in CuCrLnS (Ln = Dy-Lu) solid solutions. The charge distribution on the matrix elements (Cu, Cr, and S) remained unaffected after cationic substitution. The sulfur atoms were found to be in the S oxidation state, the copper-Cu, and the chromium-Cr.

Charge Distribution in Layered Lanthanide-Doped CuCrLnS (Ln = Pr-Tb) Thermoelectric Materials.

The charge distribution study of metal atoms in CuCrLnS (Ln = Pr-Tb) solid solutions was carried out using X-ray photoelectron spectroscopy (XPS). The analysis of the binding energy of S2p, Cu2p, Cr2p, Ln3d and Ln4d levels allows one to determine the oxidation state of atoms. Copper atoms were found to be monovalent.

High-Temperature Spin Crossover in Iron(II) Complexes with 2,6-Bis(1-imidazol-2-yl)pyridine.

Novel iron(II) coordination compounds containing a ligand 2,6-bis(1-imidazol-2-yl)pyridine (L), having such a composition as [FeL]SO·0.5HO, [FeL]Br·HO, [FeL](ReO), [FeL]BH∙HO, [FeL]BH∙1.5HO had been synthesized and studied using UV-Vis (diffuse reflectance), infrared, extended X-ray absorption fine structure (EXAFS), and Mössbauer spectroscopy methods, as well as X-ray diffraction and static magnetic susceptibility methods.

Magnetic Properties of Novel Layered Disulfides CuCr0.99Ln0.01S2 (Ln = La…Lu).

The comprehensive study of the lanthanide-doped solid solutions CuCrLnS (Ln = La…Lu) magnetic properties was carried out using static magnetochemistry and differential scanning calorimetry techniques. It was shown that magnetic properties of CuCrLnS are significantly affected by the magnetic properties of the lanthanide ion. The magnetic susceptibility and the effective magnetic moment were found to deviate from the Curie-Weiss law in the temperature 90 K below and 50 K above the order-disorder transition at 695 K.

Effect of the Order-Disorder Transition on the Electronic Structure and Physical Properties of Layered CuCrS.

The work reports a comprehensive study of the Seebeck coefficient, electrical resistivity and heat capacity of CuCrS in a wide temperature range of 100-740 K. It was shown that the value of the Seebeck coefficient is significantly affected by the sample treatment procedure. The order-to-disorder (ODT) phase transition was found to cause a metal-insulator transition (MIT).

Investigation of electronic structure of tri- and tetranuclear molybdenum clusters by X-ray photoelectron and emission spectroscopies and quantum chemical methods.

Charge state studies of compounds [MoS(tu)(HO)]Cl·4HO (1), [MoSCl(dbbpy)]Cl·5HO (2), [MoS(CuCl)Cl(dbbpy)][CuCl] (3), containing {MoS} and {MoCuS} cluster cores bearing terminal thiourea (tu) or 4,4'-di-tert-butyl-2,2'-bipyridine (dbbpy) ligands, have been performed by X-ray photoelectron and X-ray emission spectroscopies combined with quantum chemical calculations. The best agreement between theory and experiments has been obtained using the B3LYP method. According to the experimental and calculated data, the Mo atoms are in the oxidation state 4+ for all compounds.