Hyperfine structure in the X8, A[19.1]9 and B[21.68]8 states of HoF and X8 and A[15.6]9 state of HoCl

Abstract

High resolution spectra of holmium monofluoride, HoF and holmium monochloride, HoCl, prepared in a laser ablation source, have been obtained using laser induced fluorescence. Spectra of the A[19.1]9–X8 0-0 and 1-0 and B[21.68]8–X8 0-0 bands of HoF and the A[15.6]9–X8 0-0 band of HoCl all show resolved hyperfine structure. Analysis of the spectra yielded magnetic hyperfine parameters, h=0.2240(5), 0.2210(6), 0.2177(6) and 0.2488(5)cm−1 for the X (v=0), A (v=0 and 1) and B (v=0) states of HoF and 0.2355(32) and 0.2448(29)cm−1 for the X (v=0) and A (v=0) states of HoCl, respectively. The following quadrupole coupling constants were obtained for the above six states; eQq0(HoF)=−0.0874(67), −0.0586(44), −0.0579(56), −0.0840(64)cm−1 and eQq0(HoCl)=−0.082(11), −0.060(11)cm−1. Comparison with previously determined values for HoO and HoS show that the ground state magnetic hyperfine structure in HoF and HoCl is entirely due to the Ho 4f electron and is consistent with the ground state, X8, configuration of Ho+{4f10(5I8)6s2}X− (X=F,Cl). Calculations of the ground state magnetic, h(X8), and quadrupole, eQq0(X8) hyperfine parameters from atomic hyperfine parameters are found to be consistent with the observed values for both molecules.