Spin-crossover in coordination compounds of iron(II) with tris(pyrazol-1-yl)methane and cluster anions

Abstract

Synthesis procedures for new coordination compounds of iron(II) with tris(pyrazol-1-yl)methane (HC(pz)3), containing cluster anions in the outer sphere, of the composition [Fe{HC(pz)3}2][Mo6Cl14]•2H2O (I), [Fe{HC(pz)3}2][Mo6Br14]•H2O (II), and [Fe{HC(pz)3}2]2[Re6S8(CN)6]•2H2O (III) are developed. The compounds are studied by static magnetic susceptibility, electronic, IR, and Mossbauer spectroscopic methods. The magnetochemical study shows that in the polycrystalline phases of all compounds the spincrossover 1А1 ⇔ 5Т2 is observed which is accompanied by thermochromism.