Investigations on the spin-crossover complex Fe(bzimpy)2(ClO4)2and its Mn2+, Co2+, Ni2+and Zn2+analogues

摘要

A series of transition metal complexes M(bzimpy)2(ClO4)2(M=Mn2+, Fe2+, Co2+, Ni2+, Zn2+;bzimpy=2,6-bis(benzimidazol-2′-yl)pyridine) was synthesized and characterized by elemental analysis, UV-Vis and far-IR spectroscopy. The electronic spectra of Ni(bzimpy)2(ClO4)2in solution and solid state reveal a ligand field splitting parameter Δ0in the range of 11470 cm−1to 11840 cm−1. The simultaneous existence of two species with distinct spin state is found for Fe(bzimpy)2(ClO4)2by means of variable temperature far-IR measurements. Assignments of the observed far-IR bands are given on the basis of the investigations of the variation of the metal ion in M(bzimpy)2(