Molecular complexes of substituted aryl diphenylmethyl sulphides with π-acceptors. Charge transfer spectra and ionization potentials of the donors

Abstract

Charge transfer complexes of substituted aryl diphenylmethyl sulphides, X¹C₆H₄(X²C₆H₄) CH—S—C₆H₄Y, with tetracyanoethylene, 2,3-dichloro-5,6-dicyano-p-benzoquinone and chloranil have been studied spectrophotometrically. The energy of the charge transfer transition is influenced by the substituents in Y, but is not affected by the substituents in X. The ionization potentials calculated from the energy of charge transfer transitions are in good accord with those measured by photoelectron spectroscopy. The nature of the donor orbitals is also discussed.