On the scattering of low‐energy electrons by sulphur hexafluoride

The collision between a beam of electrons and gaseous molecules of sulphur hexafluoride (SF6) are studied from a theoretical and computational point of view, by solving the multichannel scattering problem within the close‐coupling (CC) approach that uses a symmetry‐adapted, single‐center‐expanded (SCE) description of the continuum functions. The static and exchange interactions are treated exactly within the basis set expansion and correlation forces are introduced in local form using a density functional model (FEG) without empirical parameters. Elastic observables (rotationally summed) are obtained over a broad range of energies, both for the integral and differential cross sections, and compared with the existing experiments. The symmetry and nature of the observed resonances are analyzed and discussed. One finds, in general, very satisfactory accord between the present calculations and the measured cross sections.

[1]  T. Stoecklin,et al.  Electron scattering from acetylene: elastic integral and differential cross sections at low energies , 1994 .

[2]  F. Fehsenfeld Electron Attachment to SF6 , 1970 .

[3]  Joseph L. Dehmer,et al.  Evidence of Effective Potential Barriers in the X‐Ray Absorption Spectra of Molecules , 1972 .

[4]  McKoy,et al.  Low-energy electron scattering by silane (SiH4). , 1990, Physical review. A, Atomic, molecular, and optical physics.

[5]  F. Gianturco,et al.  Computational methods for electron-molecule collisions , 1995 .

[6]  D. W. Norcross,et al.  Ro-vibrational excitation of HCl by electron impact , 1984 .

[7]  R. Moccia,et al.  Electronic properties of the SF6 molecule: Ab-initio calculation for the ground state☆ , 1971 .

[8]  K. Rohr Vibrational excitation of SF6 by low-energy electron impact , 1977 .

[9]  R. J. Van Brunt,et al.  Electron‐transport, ionization, attachment, and dissociation coefficients in SF6 and its mixtures , 1988 .

[10]  G. Schulz,et al.  Temperature dependence of electron attachment at low energies for polyatomic molecules , 1973 .

[11]  L. Christophorou,et al.  Low energy electron attachment to SF6 in N2, Ar, and Xe buffer gases , 1989 .

[12]  Hiroshi Tanaka,et al.  Vibrational excitation of ethane by electron impact , 1990 .

[13]  R. E. Kennerlya,et al.  The total absolute electron scattering cross sections for SF6 for incident electron energies between 0.5 and 100 eV including resonance structure , 1979 .

[14]  D. Field,et al.  Low-energy electron scattering by SF6 , 1992 .

[15]  C. Guidotti,et al.  Electronic Properties of Sulphur Hexafluoride. II. Molecular Orbital Interpretation of Its X‐Ray Absorption Spectra , 1972 .

[16]  F. Gianturco,et al.  Electron-methane scattering via a parameter-free model interaction , 1987 .

[17]  G. Moe,et al.  The Absorption Spectrum of Sulfur Hexafluoride in the Vacuum Ultraviolet Region , 1951 .

[18]  Nico Sanna,et al.  Calculation of low‐energy elastic cross sections for electron‐CF4 scattering , 1994 .

[19]  C. Kuyatt,et al.  Absorption Spectrum of SF6 in the Far Ultraviolet by Electron Impact , 1966 .

[20]  I. Gyémánt,et al.  Resonances in the elastic electron-SF6 molecule scattering , 1980 .

[21]  F. Gianturco,et al.  Exact-exchange treatment in electron-polyatomic molecule collisions in a computationally optimized iterative scheme , 1991 .

[22]  H. Ehrhardt,et al.  Electron collisions with molecules, clusters, and surfaces , 1994 .

[23]  J. Gauyacq,et al.  The attachment of very slow electrons to polyatomic molecules , 1984 .

[24]  A. Chutjian,et al.  Electron impact excitation of SF6 , 1977 .

[25]  H. Itoh,et al.  Electron swarm development in SF6. I. Boltzmann equation analysis , 1988 .

[26]  D. Dill,et al.  Shape resonances in e–SF6 scattering , 1978 .

[27]  A. Duncan,et al.  Effect of Pressure on Intensity of Some Electronic Transitions in SF6, C2H2and C2D2Vapors in the Vacuum Ultraviolet Region1 , 1954 .

[28]  F. A. Gianturco,et al.  Electron scattering from nonlinear molecules using multicentre wavefunction expansions , 1992 .

[29]  W. Newell,et al.  Absolute elastic differential cross sections for electron scattering from SF6 , 1991 .

[30]  R. Lucchese Effects of interchannel coupling on the photoionization cross sections of carbon dioxide , 1990 .

[31]  G. Diercksen,et al.  The electronic structure of molecules by a many-body approach: VI. The assignment of the HeII photoelectron spectrum of SF6 , 1975 .

[32]  H. Hotop,et al.  Attachment of electrons to molecules at submillielectronvolt resolution , 1992 .

[33]  I. Gyémánt,et al.  Total cross section of the SF6 molecule for elastic electron scattering , 1978 .