X-ray spectral and quantum chemical study of the electronic structure of thiacalix[4]-arenes and their acyclic analogs

Abstract

An X-ray photoelectron and X-ray emission study of the charge state of thiacalix[4]arenes is performed with a comparison with the data of quantum chemical calculations. Relaxation corrections between the Kohn-Sham orbital energies calculated by the DFT method and experimental parameters of the X-ray emission and photoelectron spectra of the studied compounds are estimated. It is shown that the formation of a cyclic aromatic system in thiacalixarenes results in a decrease in the energy of orbitals involving р-π interactions of the bridging sulfur atoms and aromatic moieties, which determines the features of the X-ray emission spectra of the studied compounds.