title: Synthesis and spectral investigations of Mn(II) complexes of pentadentate bis(thiosemicarbazones).
abstract: Five Mn(II) complexes of bis(thiosemicarbazones) which are represented as [Mn(H(2)Ac4Ph)Cl(2)] (1), [Mn(Ac4Ph)H(2)O] (2), [Mn(H(2)Ac4Cy)Cl(2)].H(2)O (3), [Mn(H(2)Ac4Et)Cl(2)].3H(2)O (4) and [Mn(H(2)Ac4Et)(OAc)(2)].3H(2)O (5) have been synthesized and characterized by elemental analyses, electronic, infrared and EPR spectral techniques. In all the complexes except [Mn(Ac4Ph)H(2)O], 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)H(2)O], 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)H(2)O] showing zero field splitting.
authors.affiliation: Department of Applied Chemistry, Cochin University of Science and Technology, Kochi 682022, Kerala, India.
authors.forename: Suja
authors.initials: S
authors.lastname: Krishnan
authors.forename: K
authors.initials: K
authors.lastname: Laly
authors.forename: M R
authors.initials: MR
authors.lastname: Prathapachandra Kurup
mesh_terms: D004578:Electron Spin Resonance Spectroscopy; D008345:Manganese / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism*; D013055:Spectrophotometry, Infrared; D013882:Thiosemicarbazones / Q000138:chemical synthesis* / Q000737:chemistry*
chemical_list: D009942:Organometallic Compounds; D013882:Thiosemicarbazones; D008345:Manganese