Structure and physical properties of hexacyanomanganate(III), [Mn III(CN) 6] 3−

Abstract

Organic soluble [(Ph 3P) 2N] 3[Mn III(CN) 6] has been structurally characterized. The expected Jahn–Teller distortion for this low-spin ( S = 1) octahedral d 4 ion is observed as a tetragonal compression from an analysis of the structural data. Spin-orbit coupling effects are evident in temperature-dependent susceptibility and the effective moment is fit by the Kotani model using a spin-orbit parameter λ of 200 K and a temperature-independent paramagnetic, TIP, contribution of 0.000040 emu mol −1. [Mn III(CN) 6] 3− shows a reversible Mn III/IV couple at E 1/2 = + 0.14 V (corrected to SCE), Δ E pp = 0.09 V (10 mV s −1 scan rate) in MeCN. The electronic spectrum of the [Mn III(CN) 6] 3− anion in MeCN is consistent with the spectrum of this ion previously reported in aqueous media.