Infrared Spectra of Divalent Metal Monothioacetylacetonates

The infrared spectra of copper (II), nickel (II), zinc (II), palladium (II), cadmium (II), and lead (II) complexes of monothioacetylacetone have been recorded from 1700–300 cm−1. Assignments for in-plane vibrations were obtained by normal coordinate analyses. The carbon–oxygen stretching vibration was located near 710 cm−1. In every case metal–oxygen stretching force constants were larger than metal–sulfur constants and carbon–sulfur constants were less than carbon–oxygen constants. Systematic trends which appeared among both metal–sulfur and metal–oxygen stretching force constants were correlated with sequences observed among the carbon–donor atom force constants.