0181526 - UFCH-W 20020207 RIV GB eng J - Journal Article
Cascella, M. - Čurík, Roman - Gianturco, F. A.
Vibrational Excitation in Electron-CH4 Collisions: Exchange Interaction Effects.
Journal of Physics B-Atomic Molecular and Optical Physics. Roč. 34, - (2001), s. 705-723. ISSN 0953-4075. E-ISSN 1361-6455
Institutional research plan: CEZ:AV0Z4040901
Keywords : molecule-scattering * separable representation * methane
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 2.046, year: 2001

The vibrational excitations of all four normal modes of the methane molecule in collisions with low-energy electrons (E-coll < 15 eV) are computed within the adiabatic approximation for the nuclear motion and solving the quantum dynamics for the scattered electron. The non-local exchange forces are treated by a separable expansion and by a semiclassical local model and their effects on the vibrationally inelastic cross sections are examined. By comparing the (nu(1) + nu (3)) and the (nu (2) + nu (4)) sums of the four vibrationally inelastic modes as two sets of ''''stretching'''' and ''''bending'''' modes, with existing experiments on the latter, we are able to show that both approaches produce rather good accord with the available data, while presenting differences in them. The local model for treating exchange, which affords a substantial reduction of computational time, is shown to reasonably well describe vibrational inelasticity.
Permanent Link: http://hdl.handle.net/11104/0078082