Ground-State Reduced Potential Curve (RPC) and the Anomaly of Cl2

Abstract

The study of ground‐state reduced potential curves indicates that either there is some error in the analysis of the spectrum and/or in the values of molecular constants of the Cl₂ molecule or a nonnegligible perturbation of the ground state of Cl₂ exists. In case the analysis of the spectrum and the values of the molecular constants are correct, the RPC method then leads to the following conclusion: The perturbation of the electronic states of halogens, predicted in order to explain the remarkably anomalous intensities of the band spectra, is, in I₂, of the type proposed by Van Vleck whereas, for Cl₂, the interpretation suggested by Mulliken holds.