Five Mn(II) complexes of bis(thiosemicarbazones) which are represented as [Mn(H2Ac4Ph)Cl2]
(1), [Mn(Ac4Ph)H2O] (2), [Mn(H2Ac4Cy)Cl2]·H2O (3), [Mn(H2Ac4Et)Cl2]·3H2O (4) and
[Mn(H2Ac4Et)(OAc)2]·3H2O (5) have been synthesized and characterized by elemental analyses,
electronic, infrared and EPR spectral techniques. In all the complexes except [Mn(Ac4Ph)H2O], the
ligands act as pentadentate neutral molecules and coordinate to Mn(II) ion through two thione sulfur
atoms, two azomethine nitrogens and the pyridine nitrogen, suggesting a heptacoordination. While in
compound [Mn(Ac4Ph)H2O], the dianionic ligand is coordinated to the metal suggesting six coordination
in this case. Magnetic studies indicate the high spin state of Mn(II). Conductivity measurements reveal
their non-electrolyte nature. EPR studies indicate five g values for [Mn(Ac4Ph)H2O] showing zero field
splitting.Cochin University of Science and TechnologySpectrochimica Acta Part A 75 (2010) 585–58