Core-electron Spectra of Mono-substituted Benzenes Obtained by the Gas-phase X-Ray Photoelectron Spectroscopy

Abstract

The gas-phase X-ray photoelectron spectra were observed on benzene and its eight mono-substituted derivatives; C₆H₅X, X=H, CH₃, NH₂, OH, F, Cl, Br, NO₂ and CN. Binding energies of core levels were determined from the observed spectra by using the spectrum simulation technique, and they were compared with the chemical shift predicted from the CNDO/2 charge densities on the basis of the electrostatic potential model. It is shown that the Cls binding energies of benzene derivatives can be generally correlated with atomic charges, q_j, by the following equation;