15min:
THE SUBMILLIMETER AND MICROWAVE SPECTRA OF HZnCl (X 1 Sigma+).

R. L. PULLIAM, M. SUN, M. A. FLORY, L. M. ZIURYS, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ, 85721.

The pure rotational spectra of HZnCl (1 Sigma+) has been studied using submillimeter-wave direct-absorption and Fourier transform microwave (FTMW) methods. This species was produced by the reaction of zinc vapor and Cl2 in the presence of H2 and a d.c. discharge for the millimeter studies. For the FTMW measurements, HZnCl was made by the reaction of chlorine gas and Zn(CH3)2 in a d.c. discharge created in the supersonic nozzle. The spectra of seven isotopologues were recorded including the deuterium substituted species. We were able to obtain the rotational constants of B0 and D0 for each isotopologue. Using the FTMW data, we observed the hyperfine components of the lower J transitions and determined the chlorine quadrupole constant. For HZnCl, the average Zn-Cl bond length was determined to be 2.083153(21) Å with the H-Zn bond length equal to 1.51909(38) Å. From HZnCl to its open shelled counterpart ZnCl, the bond length was found to contract by ~0.05 Å suggesting that the hydrogen stabilizes the molecule.