Rotational band shapes in photoelectron spectroscopy: HF and DF

Rotational line strengths for ionization are calculated assuming only s partial waves. Rotational band contours are then constructed by broadening each rotational line with a known instrumental line shape. This technique is applied to HF and DF, and reproduces the experimental results well, allowing an accurate value of the spin-orbit coupling constant to be extracted from experiment. The value of − 290 ± 10 cm−1 agrees with previous Hartree-Fock calculations. The ionization potentials (16.044 ± 0.003 eV for HF, 16.058 ± 0.003 eV for DF) are obtained with an accuracy one order of magnitude better than the experimental resolution, and there is some evidence for an electronic isotope shift.