MATTHEW P. BUCCHINO, Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721; AND LUCY M. ZIURYS, Department of Chemistry and Biochemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, Arizona 85721.
Sub-millimeter spectra of CaH (X2 +), MgH (X2 +), and ZnH (X2 +) have been measured in the sub-mm/THz regime (500-805 GHz) using direct-absorption methods. All species were produced by the reaction of metal vapor with H2 under DC discharge in a Broida-type oven. Because of efficient molecule production, spectra of 26MgH, 66ZnH, 68ZnH and 70ZnH could be recorded in their natural abundance as well, with high signal-to-noise. Additionally, the N = 0 1 and N = 1 2 transitions of 25MgH and 67ZnH were measured. Fermi contact, dipolar, and quadrupole constants for the 25Mg and 67Zn nuclei have been accurately determined for the first time in the gas phase, and are in good agreement with previous ESR studies. The hyperfine constants suggest a substantial amount of covalent character is present in metal hydrides.