40min:
MILLIMETER-WAVE SPECTROSCOPY OF METAL-CONTAINING MOLECULES: A DECADE OF BLOOD, SWEAT AND TELESCOPES.

L. M. ZIURYS, Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ, 85721.

Metal-containing molecules are important in a wide variety of areas, including organic synthesis, catalysis, chemical vapor deposition and in biology. They also play a significant role in interstellar chemistry, where they trace the unusual physical and chemical processes during the later stages of stellar evolution. Therefore, high-resolution measurements of the gas-phase spectra of metal-containing species impact on many fields, providing structural information, bonding characteristics and the necessary ``rest-frequencies'' for radio astronomical observations.

For over a decade, the Ziurys group has been recording pure-rotational spectra of transient metal-bearing species using millimeter/submillimeter direct absorption techniques. These molecules have been created through the gas-phase reaction of the metal vapor, produced by a modified Broida oven, with an appropriate precursor. Metals of particular interest have included lithium, sodium, magnesium, potassium, calcium, aluminum, and the 3d transition metals, combined with a variety of simple ligands such as OH, CN, CCH, CH3, NH2, and even carbon and nitrogen atoms. Several of the molecules investigated are common organic reagents such as LiCH3, NaNH2 and CuCN; others are short lived free-radicals with high-spin ground states, e.g. MnF (7 Sigma+), CoCN (3 Phii) and NaC (4 Sigma-), some of which exhibit Renner-Teller splittings or quasi-linear effects in vibrationally excited states. A large fraction of these molecules are also of astrophysical interest and have been studied in interstellar/circumstellar gas. In this talk, the interesting chemistry and spectroscopy of these species will be discussed. In addition, implications of recent astronomical identifications will be summarized.