VIBRATIONAL PREDISSOCIATION OF METHANE-Ar : AN AB-INITIO APPROACH

  1. Geleijns, M. 1
  2. Halberstadt, N. 2
  3. Millan, J. 2
  4. Wormer, P.E.S. 1
  5. Van der Avoird, A. 1
  1. 1 Radboud University Nijmegen
    info

    Radboud University Nijmegen

    Nimega, Holanda

    ROR https://ror.org/016xsfp80

  2. 2 Paul Sabatier University
    info

    Paul Sabatier University

    Tolosa, Francia

    ROR https://ror.org/02v6kpv12

Revista:
Faraday discussions Online

ISSN: 1364-5498

Año de publicación: 2001

Volumen: 118

Páginas: 143-158

Tipo: Artículo

SCOPUS: 2-s2.0-0003086491 WoS: WOS:000171466300010 GOOGLE SCHOLAR

Otras publicaciones en: Faraday discussions Online

Repositorio institucional: lock_openAcceso abierto Editor

Resumen

We calculated the cross sections for vibrational predissociation of methane-Ar induced by excitation of the methane v3 mode with the aid of an ab initio CH4-Ar potential depending explicitly on the v3 and v1 normal coordinates of the CH4 monomer. We found that dissociation into CH4 fragments excited in the v1 mode, a V → V′ process with very low kinetic energy release, strongly dominates over direct dissociation into Ar and ground state CH4, and is responsible for the line broadening observed experimentally. The (observed and calculated) strong variation of the line widths for the Van der Waals levels excited in combination with the v3 mode (giving states of A, F and E symmetry) is related to the opening up of appropriate v1 dissociation channels and the occurrence of rotational resonances in the v1 continuum in the energy range of the quasi-bound v3 levels.