Synthesis and characterization of some octahedral transition metal complexes with phenyl-2-picolylketone thiosemicarbazone

Summary A series of transition metal complexes with phenyl-2-picolylketone-thiosemicarbazone, LH, of the general formula [ML₂]Cl_nmH₂O, (M=Cr³⁺, Mn²⁺, Fe²⁺, Rh³⁺, Ir³⁺ or Ru³⁺; n=0 or 1 and m=1,2 or 3) have been prepared and characterized. Magnetic and spectral (electronic and vibrational) data are commensurate with an octahedral ligand field for all complexes. The variable temperature magnetic moment shows that the iron(II) complex exists in a temperature-dependent high-spinlow-spin equilibrium. The far i.r. spectra show that the strength of the M–S bond follows the order: Mn²⁺ 2+3+3+3+3+. The various ligand field parameters, Dq, B' and are calculated.