SUB-MILLIMETER/TERAHERTZ SPECTROSCOPY OF FeH AND FeD (X4Δi^{4}\Delta _{i})

Author Institution: Department of Chemistry and Biochemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, Arizona 85721Direct measurements of the lowest pure rotational transitions of the $\Omega$ = 7/2, 5/2, and 3/2 ladders of FeD and of the $\Omega$ = 1/2 ladder of FeH in the $^{4}\Delta_{i}$ ground electronic states have been conducted using millimeter/sub-millimeter direct absorption techniques in the frequency range 530-810 GHz. Both species were created in an AC discharge from the reaction of Fe(CO)$_{5}$ with H$_{2}$ or D$_{2}$. In several of these transitions lambda-doubling and proton/deuterium hyperfine structure have been resolved. These data improve on the zero field frequencies predicted from previous LMR data by several MHz.$^{a}$ Accurate frequencies are crucial for sub-millimeter searches for FeH toward the interstellar medium. Searches for additional transitions are in progress. \\ \\ $^{a}$ J.M. Brown, H. Korsgen, S.P. Beaton, \& K.M. Evenson, J. Chem. Phys. 124, 234309 (2006

FOURIER TRANSFORM MICROWAVE SPECTROSCOPY OF ALKALI METAL HYDROSULFIDES: DETECTION OF KSH

Author Institution: Department of Chemistry and Biochemistry, Canisius College, Buffalo, NY 14208; Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ 85721Fourier transform microwave (FTMW) techniques have been used to record pure rotational spectra of potassium hydrosulfide and its deuterium isotopologue in their ground electronic states. This study represents the first gas phase spectroscopic observation of KSH. FTMW spectra of NaSH were also recorded. The metal hydrosulfides were produced by discharge assisted laser ablation of the solid alkali metal in the presence of hydrogen sulfide or deuterated hydrogen sulfide. Rotational transitions in the 5 À_ 20 GHz range were measured and hyperfine splittings due to the alkali metals and deuterium were resolved. Rotational as well as metal and deuterium quadrupole coupling constants have been determined from the data. The hyperfine parameters will be interpreted in terms of metal-ligand bonding character. Geometric parameters of the alkali metal hydrosulfides will be compared

Examining transition metal hydrosulfides: The pure rotational spectrum of ZnSH (X̃2A′)

The pure rotational spectrum of the ZnSH ((X) over tilde (2)A') radical has been measured using millimeter-wave direct absorption and Fourier transform microwave (FTMW) methods across the frequency range 18-468 GHz. This work is the first gas-phase detection of ZnSH by any spectroscopic technique. Spectra of the (ZnSH)-Zn-66, (ZnSH)-Zn-68, and (ZnSD)-Zn-64 isotopologues were also recorded. In the mm-wave study, ZnSH was synthesized in a DC discharge by the reaction of zinc vapor, generated by a Broidatype oven, with H2S; for FTMW measurements, the radical was made in a supersonic jet expansion by the same reactants but utilizing a discharge-assisted laser ablation source. Between 7 and 9 rotational transitions were recorded for each isotopologue. Asymmetry components with K-a = 0 through 6 were typically measured in the mm-wave region, each split into spin-rotation doublets. In the FTMW spectra, hyperfine interactions were also resolved, arising from the hydrogen or deuterium nuclear spins of I = 1/2 or I = 1, respectively. The data were analyzed using an asymmetric top Hamiltonian, and rotational, spin-rotation, and magnetic hyperfine parameters were determined for ZnSH, as well as the quadrupole coupling constant for ZnSD. The observed spectra clearly indicate that ZnSH has a bent geometry. The r(m)((1)) structure was determined to be r(Zn-S) = 2.213(5) angstrom, r(S-H) = 1.351(3) angstrom, and theta(Zn-S-H) = 90.6(1)degrees, suggesting that the bonding occurs primarily through sulfur p orbitals, analogous to H2S. The hyperfine constants indicate that the unpaired electron in ZnSH primarily resides on the zinc nucleus. Published by AIP Publishing.NSF [CHE-1565765]12 month embargo; Published online: 20 October 2017This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]