Spin-crossover in iron(ii) coordination compounds with 2,6-bis(benzimidazol-2-yl)pyridine

Abstract

New iron(II) complexes with 2,6-bis(benzimidazol-2-yl)pyridine (L), in particular, [FeL₂]A₂·nH₂O (A = Br⁻ (I), NO₃⁻ (II), C₂N₃⁻ (III); n = 1 (I), 0.5 (II), 2 (III)) and [NiL₂]Br₂·1.23H₂O·3.33EtOH (IV), have been synthesized and studied using single-crystal and powder X-ray diffraction techniques, UV-vis (diffuse reflection), IR and Mössbauer spectroscopy, as well as static magnetic susceptibility measurements. According to the experimental μ_eff(T) curves all the studied iron(II) compounds exhibit ¹A₁ ↔ ⁵T₂ spin-crossover.