Magnetic properties and vapochromism of a composite on the base of an iron(II) spin crossover complex

Abstract

A polymeric iron(II) complex, Fe(ATrz)3(NO3)2·nH2O (ATrz = 4-amino-1,2,4-triazole), can be embedded in the polystyrene matrix to form a composite spin crossover material. This composite material can be prepared in the form of films with a thickness of ca. 10–20 μm. The material demonstrates two spin crossover regimes (with and without thermal hysteresis) and reversible switching between these regimes, thermochromic effect (pink – white) and vapochromic behavior in the atmosphere of HCl, NH3, HNO3 and HBr vapors.