High resolution studies of low-energy electron attachment to SF5Cl: Product anions and absolute cross sections

Low energy electron attachment to SF$_5$Cl was studied at high energy resolution by mass spectrometric detection of the product anions. Two variants of the laser photoelectron attachment (LPA) technique (Kaiserslautern) were used for determining the threshold behaviour of the yield for SF$_5^-$ formation at about 1 meV resolution, and to investigate the relative cross sections for Cl$^-$, FCl$^-$, and SF$_5^-$ formation towards higher energies (up to 1 eV) at about 20 meV resolution. Thermal swarm measurements (Birmingham) were used to place the relative LPA cross sections on an absolute scale. A trochoidal electron monochromator (Innsbruck) was used for survey measurements of the relative cross sections for the different product anions over the energy range of 0-14 eV with a resolution of 0.30 eV. Combined with earlier beam data (taken at Berlin, J. Chem. Phys. 88 (1988) 149), the present experimental results provide a detailed set of partial cross sections for anion formation in low-energy electron collisions with SF$_5$Cl

INFRARED SPECTRUM OF THE PRODUCTS OF THE INTERACTION OF EXCITED NEON ATOMS WITH CCl4CCl_{4} TRAPPED IN SOLID NEON

$^{a}$ G. Maier, H.P. Reisenauer, J. Hu, B.A. Hess, Jr., and L.J. Scha***d, Tetra***ed, Lett, 30, 4105 (1989).Author Institution: National Institute of Standards and TechnologyWhen a $Ne:CCl_{4}$ sample is codeposited at approximately 5 K with a beam of neon atoms that have been excited in a microwave discharge, the infrared spectrum of the resulting solid deposit shows prominent absorptions that have previously been $assigned^{a}$ to $Cl_{2}CCl-Cl$, as well as other absorptions of uncharged, cationic $CCl_{a} (n= 1-3)$ and anionic $CCl_{n} (n=3,4)$ species. Studies of $Ne:^{1}3CCl_{4}$ samples and studies of the photodestruction of the products when the deposit is subjected to various bands of visible and ultraviolet radiation support the proposed assignments

HIGH RESOLUTION SPECTROSCOPY OF CH2F2CH_{2}F_{2} IN THE 3 μ\mum REGION. THE 2vg BAND AT 2839cm−12839 cm^{-1}.

$^{(1)}$M. Carlotti, G.D. Nivellini, F. Tullini, and B. Carli, J. Mol. Spectrosc. 132, 158-165 (1988) $^{(2)}$M. N. Deo, R. D'Cunha, and A. Weber, analysis reported at the 1994 Columbus meeting, paper RH08Author Institution: Molecular Physics Division, National Institute of Standards and TechnologyThe infrared absorption spectrum of methylene fluoride ($CH_{2}F_{2}$) has been recorded at a spectral resolution of $0.004 cm^{-1}$ in the region from 2700 to $3300 cm^{-1}$ with the BOMEM DA3.002 Fourier transform spectrometer at NIST. The 2vg band, centered at $2838.6 cm^{-1}$, has been analyzed in detail and the analyses of the $v_{1}$ and $(v_{2}+v_{8})$ bands at $2948 cm^{-1}$ and $2943 cm^{-1}$, respectively, are underway. The 2vg band is quite perturbed, but using the non- and only slightly perturbed transitions it has been possible to obtain a least squares fit using the Watson A-reduction Hamiltonian. The ground state constants were constrained to the values reported by Carlotti, $et al.^{(1)}$ 1159 transitions with J and K values ranging up to 44 and 22, respectively, were used in the fit. The resulting upper state constants reproduce the experimental data (the non- and only slightly perturbed transitions) with a standard deviation of $0.00034 cm^{-1}$. Full use of all observed transitions will require the inclusion of x,y-type Coriolis interaction with the $v_{6}$ $fundamental^{(2)}$ and a z-type Coriolis transitions coupling with the $v_{2}+v_{8}$ combination band. Work on these bands is in progress