Vanadocene(IV) dicyanide complexes: the evidence super-hyperfine coupling for compounds with 13CN ligands.

An EPR study of the vanadocene complexes (C(5)H(5))2V(CN)2 and (CH(3)C(5)H(4))2V(CN)2 was carried out. Such compounds show strong super-hyperfine coupling (|a(iso)(13C)| approximately 1.27 mT) when 13C labeled cyanide is used for their preparation. Super-hyperfine splitting was observed in the isotropic spectra of solution samples as well as in the anisotropic spectra of frozen solutions. Such studies were supplemented with structural characterization of the parent compounds. Molecular structure of the complex (CH(3)C(5)H(4))2V(CN)2 was determined by single-crystal X-ray diffraction analysis. Both compounds were characterized by infrared and Raman spectroscopy.