Magnetic Properties of Some Triangular Trinuclear Complexes of [Ru2M(μ-CH3COO)6(μ3-O)(py)3]n+ with a Paramagnetic Ion M

Abstract

Abstract Magnetic susceptibilities and electron paramagnetic resonances (EPRs) of coordination compounds of triangular trinuclear [Ru2M(μ-CH3COO)6(μ3-O)(py)3]n+, M = Mn(II), Fe(III), Cr(III), Ni(II), or Co(II) ions, were observed. The results were analysed by the spin vector model. Effective Bohr magneton numbers showed that the main superexchange interaction within each cluster was of the order of J/k = −300 K. This was considered to be working through μ3-O. Together with some weaker superexchange interactions through μ-CH3COO paths, fittings with the susceptibilities of the model were tried. EPR signals at temperatures of a few K were characteristic of each M ion. M = Mn(II) and M = Fe(III) were at high spin states of S = 5/2 and M = Co(II) was at a low spin state of S = 1/2. Temperature dependences of EPR signals are discussed.