Electronic spectroscopy of N-ylids

Electronic absorption and fluorescence spectra of some cycloimmonium ylids with different heterocycles or with different substituted carbanions are used to establish some structural features of these zwitterionic compounds. The nature of intermolecular interactions in different solvents and the contribution of the each kind of interaction in solvation energy are estimated. The structure of cycloimmonium ylid solvation sphere in ternary solutions is also established by spectral means. The microscopic parameters (dipole moments and polarizabilities) of ylid molecules are estimated by fitting the wavenumbers of the intramolecular charge transfer band with functions describing solvent influence on electronic molecular spectra. q 2004 Elsevier B.V. All rights reserved.