Computing vibrational effects in low-energy positron scattering from polyatomic molecules: the H2O and C2H2 stretching modes

Autor: Franco A. Gianturco, Tamio Nishimura
Rok vydání: 2004
Předmět:
Zdroj: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms. 221:24-29
ISSN: 0168-583X
Popis: We report a theoretical study and the computational results on vibrational excitations by positron impact of the polyatomic molecules CH 4 and C 2 H 2 as examples. The study has been carried out using the body-fixed vibrational close-coupling (BF-VCC) method which is relevant for describing vibrationally inelastic processes in low-energy collisions. The interaction potential we employ to model the forces at play is described in detail and we also report our numerical techniques for solving the scattering equations. The cross-sections are obtained for the vibrational excitations of the symmetric ( ν 1 ) and the antisymmetric ( ν 3 ) stretching modes of the H 2 O molecule and for the symmetric stretching ( ν 1 ) mode of C 2 H 2 , and they are compared with simpler available approximations.
Databáze: OpenAIRE