JOURNAL OF MOLECULAR SPECTROSCOPY 185, 290–295 (1997) ARTICLE NO. MS977424 Far-Infrared Rotational Spectra of ZnH and ZnD

Several rotational transitions of zinc hydride and deuteride within the £ 0 level of the X 2S / state have been measured in both electron spin components over the ranges N 9 2 to 10 for ZnH and N 9 9 to 21 for ZnD. A least-squares fit to these data in combination with low-N microwave data measured by other workers has resulted in improved values of the rotational, fine, and hyperfine structure constants. The values of the proton hyperfine constants are discussed in the context of a molecular orbital analysis of zinc hydride. q 1997 Academic Press INTRODUCTION meaningful comparison with theory on this issue will require additional accurate measurements of pure rotational transi-tions of several isotopomers in excited vibrational levels. InIn this paper we describe the measurement of the pure rotational spectrum of six isotopomers of zinc hydride in its the present work, we report improved values for the rota-tional, spin–rotation, and magnetic hyperfine parameters ofX 2S / ( £ 0) level by tunable far-infrared spectroscopy