Integral intensities of thiocyanate groups and the type of their coordination in metal complexes with pyrazolone derivatives

Measured have been the frequencies and integral intensities in the antisymmetric valent oscillation bands of the thiocyanate group in the infrared spectra of the Pt4, Pt2, Pd2, Ln2, Cd2, Mn2, Fe2, Co2, Ni2 and Jn3 complexes. These complexes contain organic ligands (1-phenyl-2.3-dimethyl pyrazolone-5) and thiocyanate groups in the crystalline state (in KBr tablets). It has been found that the low value of Asup(as)(NSCsup(-))=1.0-3.0x10sup(4) kg/molxcm2 per group is the criterion for the coordination of the thiocyanate groups with metal via the sulfur atom. The value of Asup(as)(NSCsup(-))=19-31x10sup(4) kg/molxcm2 is the criterion for the metal-nitrogen bond. It is shown that in the crystalline state the thiocyanate group develops the metal-sulfur-type bonds with Pt4, Pt2 and Pd2 metals. However, the metal-nitrogen-type bond is formed with the Zn2, Cd2, Jn2, Mn2, Fe2, Co2 and Ni2 metals