Magneto-structural correlation and low temperature heat capacity of a Mn (III) quadridentate Schiff-base coordination compound

Abstract

A new Mn (III) Schiff-base coordination compound, [Mn(L)(NCS)]2 (H2L=N,N′-bis(5-chlorosalicylidene)-1,2-diaminoethane), has been synthesized and characterized structurally and magnetically. The target compound is a phenoxo-bridged dimeric compound with the isothiocyanate coordinating in a usual bent mode. A magnetic susceptibility study reveals that the target compound exhibits antiferromagnetic intra-dimer coupling between Mn (III) ions. The low temperature heat capacity of the compound over the temperature range (2 to 300)K has been measured using the heat capacity option of a Quantum Design Physical Property Measurement System (PPMS). The thermodynamic functions in the experimental temperature range have been determined by curve fitting. The standard entropy and enthalpy of the as-prepared compound at T=298.15K have been calculated to be (924.52±10.17)J·K−1·mol−1 and (133.47±1.47)kJ·mol−1, respectively.