Electron-impact vibrational excitation of polyatomic gases: Exploratory calculations

نویسندگان

  • M. Cascella
  • R. Curik
  • F. A. Gianturco
چکیده

We present model calculations for the inelastic cross sections of electron collisions with tetrahedral molecules XH4 ~X5C, Si, Ge! when only the molecular ‘‘breathing’’ mode, n1 , is being excited. The collision energy range is well above the excited thresholds and up to 12 eV, where the adiabatic approximation for the inelastic T matrix is expected to hold. The results show the efficiency of the t2 shape resonance in enhancing the inelastic process and the appearance, in the two heavier targets, of a further a1 resonance in the inelastic channels of both molecules. The corresponding excitation rates are also computed together with estimates of the vibrational excitation functions. © 2001 American Institute of Physics. @DOI: 10.1063/1.1336567#

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تاریخ انتشار 2001