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 study of the µ(T) dependence showed that the A ↔ T spin crossover manifests itself in the compounds. The spin crossover is accompanied by thermochromism: there is a distinct color change orange ↔ red-violet.