https://doi.org/10.1140/epjd/e2006-00115-2
Vibrational excitation of acetylene by positron impact
The totally symmetric modes at near-threshold energies
Department of Chemistry, University of Rome La Sapienza, Piazzale A. Moro 5, 00185 Rome, Italy
Corresponding author: a fa.gianturco@caspur.it
Received:
30
March
2006
Revised:
20
April
2006
Published online:
18
May
2006
Vibrationally inelastic quantum calculations are carried out at low collision energies for the scattering of a beam of positrons off acetylene gaseous molecules. The normal mode analysis is assumed to be valid and the relative fluxes into the C–C and C–H symmetric vibrational modes are computed within a Body-Fixed (BF) formulation of the dynamics by solving the relevant vibrational Coupled Channels (VCC) equations. The clear dominance of the C–C mode is observed near threshold and the implications of this finding are briefly considered in relation to more global indicators like the average vibrational energy transfer indices as obtained in the present work.
PACS: 34.10.+x – General theories and models of atomic and molecular collisions and interactions (including statistical theories, transition state, stochastic and trajectory models, etc.) / 36.10.Dr – Positronium, muonium, muonic atoms and molecules / 82.30.Gg – Positronium chemistry
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2006
