A reassignment of the gas-phase photoelectron spectra of the actinide tetrahalides UF4, UCl4, ThF4 and ThCl4 by relativistic hartree-fock-slater calculations

Abstract

Geometry optimization calculations have been performed for the actinide tetrahalides UF4, UCl4, ThF4 and ThCl4 using the relativistic Hartree-Fock-Slater method. These molecules are computed to have tetrahedral equilibrium geometries in their ground states. The uranium compounds, however, are found to have an open-shell ground state and could therefore exhibit a Jahn-Teller distortion away from tetrahedral symmetry. Assuming a tetrahedral geometry for these molecules, vertical ionization energies have been computed and this has led to a partial reassignment of the molecular gas-phase photoelectron spectra.