Hyperfine structure of the BaIXthinsp;2Sgr;+andCthinsp;2Pgr; states

摘要

Opticalhyphen;microwave double resonance measurements were carried out to find the hyperfine structure constants of thev=0 level of the BaIXthinsp;2Sgr;+state. These were combined with subhyphen;Doppler optical measurements of the BaICthinsp;2Pgr;ndash;Xthinsp;2Sgr;+(0,0) band in order to derive the hyperfine structure constants of the excited state. We have determined the following molecular constants (in MHz) where the numbers in parentheses represent one standard deviation in a least squares fit: for the BaIXthinsp;2Sgr;+state, ggr;lsquo;=75.8501(33),blsquo;=93.117(19),clsquo;=52.170(54), andeQqlsquo;=minus;33.62(12), and for the BaICthinsp;2Pgr; state,arsquo;=263(53),brsquo;+crsquo;=minus;430(212),drsquo;=minus;66.7(1.4), andeQqrsquo;=minus;214(11). The Fermi contact interaction and the electric quadrupole coupling constants for both the BaIXandCstates appear to arise from the distortion of closedhyphen;shell Iminus;orbitals by the field of the Ba+ion. In the BaIXstate, the charge distribution on the Ba+center is directed away from Iminus;while in theCstate toward Iminus;.