Structure and physical properties of hexacyanomanganate(III), [MnIII(CN)6]3-

Organic soluble [(Ph3P)(2)N]](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 lambda 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), Delta 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. (C) 1999 Elsevier Science S.A. All rights reserved.