MOLECULAR MODELING OF THE INFLUENCE OF COMPLEX-FORMATION ON THE CONFORMATION AND ELECTRONIC ABSORPTION-SPECTRA OF CROWN-CONTAINING STYRYL DYES

The conformation and electronic absorption spectra of crown-containing styryl dyes and their complexes with metal salts have been calculated . The long-wave absorption bands have been assigned. It was shown that the observed large hypsochromic shift of the absorption spectra durin g the formation of complexes of the cis-form of the dyes under conside ration with alkaline earth ions is due to a change in the conformation of the chromophore and the resultant approximate prohibition with res pect to symmetry of the long-wave electronic transition.