Synthesis, spectral and magnetic studies of some polynuclear, mixed-ligand complexes of iron and cobalt with 3-mercaptopropionic acid

摘要

Some mixed-ligand, trinuclear complexesof mixed-valence iron (III, III, II) and dinuclear cobalt(II) have been synthesized by enforced substitution of acetate ions from their respective acetato complexes. The isolated products of the types [Fe_3O(OOCR)_3(OOCR'SH)_3] and [Co(OOCR)(OOCR'SH)]_2 (where R = C_7H_15, C_11H_23 or C_15H_31 and R' = -CH_2CH_2-) are mixed (carboxylato)(mercaptocarboxylato) complexes. These have been characterized by microanalytical data and infrared, UV-visible and Mossbauer spectra. Non-electrolytic behaviour and polynuclear nature of the complexes have been assessed from their low conductance and high molecular weight data. The octahedral environment around both the metals has been suggested on the basis of UV-visible and magnetic moment data. Mossbauer studies reveal two resolved quadrupole doublets due to Fe(II) and Fe(III) confirming the valence-localised classification of the iron compounds.