Infrared Spectra of Metal (II) Complexes of 1, 3, 4-Thiadiazole-2, 5-Dithiol, 5-Amino-L, 2, 4-Dithiazol-3-Thione and Their Acetyl Derivatives

Abstract

An infrared spectral interpretation of the structure of fifteen solid complexes formed by Co(II), Cu(II), Cd(II), Hg(II), Pb(II) and Zn(II) with ligands 1, 3, 4-thiadiazole-2, 5-dithiol (bismuthiol), 5-amino-l, 2, 4-dithiazolin-3-thione (xanthane) and the 2-acetyl-l, 3, 4-thiadiazol-5-thione and 5-acetylamide-l, 2, 4-dithiazol-3-t)thione derivatives is performed. The coexistence of different tautomers of bismuthiol and xanthane in the solid state is proposed. The bismuthiol-metal complexes display a unique and similar polymeric structure involving one tautomer. The xanthane-metal complexation stabilizes the 1, 1-dithiolate-type polymeric species; complexation with Cd, Co and Hg metal ions also stabilizes polymers involving the perthiocyanic teutomer.

Key Words:

• 1,3,4-thiadiazole-2,5-dithiol
• 5-amino-1,2,4-dithiazol-3-thione
• bismuthiol
• xanthane
• infrared band assignment
• tautomerism
• complex structure.