Synthesis, structure and physico-chemical studies of Mn (II) complexes of salicylaldehyde derived semicarbazone and thiosemicarbazone

Complexes of semicarbazone and thiosemicarbazone of salicylaldehyde with Mn(II) have been synthesized by ethanolic solution of 0.05 mole of MnCl2.4H2O and 0.1 mole of corresponding ligand (ie, semi and thiosemciarbazone). Crystal data are reported with variable coordination modes. The complexes have been characterized by various physico-chemical techniques, viz. magnetic susceptibility measurement, electronic, infra-red and electron spin resonance spectral studies. These complexes are found of the type of Mn (ligand)2 X2 {X = Cl-1, Br , So42- and SCN-1 }. All the complexes show a very good agreement with standard magnetic moment value of complexes having five unpaired spins at room temperature They show magnetic moments in the range of 5.93 – 6.03 BM at room temperature. Electronic spectra of the complexes display weak absorption bands in the range 18200-20400 cm-1, 21060-25100 cm-1, 24870-29860 cm-1, 31300-33350 cm-1 which are characteristics of octahedral geometry .