Cross sections and values for ligand-field-split Br 3d orbitals in HBr

Abstract

The ligand field in HBr results in the splitting of the Br 3d orbitals into the 3d (dx2-y2, dxy), 3d (dxz, dyz), and 3d (dz2) orbitals. In core ionized HBr, the stronger spin-orbit splitting removes the remaining degeneracies and results in five different Br 3d eigenstates from linear combinations of the 3d, 3d, and 3d orbitals. In high-resolution Br 3d photoelectron spectra, as presented in this work, these five peaks are resolved. The photoelectron cross sections and values for the different d orbitals have been studied from 5 to 25 eV above threshold. The relative intensities for the different 3d orbitals are quite different at different analysis angles, showing that the values are different. Multiple-scattering-X calculations give results in semiquantitative agreement with experiment.