Linewidths of C2H2 perturbed by H2: experiments and calculations from an ab initio potential.
In this work we present a theoretical and experimental study of the acetylene-hydrogen system. A potential surface considering rigid monomers has been obtained by ab initio quantum chemistry methods. This 4-dimensional potential is further employed to compute, using the close-coupling approach and the coupled-states approximation, pressure broadening coefficients of C2H2 isotropic Raman Q lines over a temperature range of 77 to 2000 K. Experimental data for the acetylene nu2 Raman lines broadened by molecular hydrogen are obtained using stimulated Raman spectroscopy. The comparison of theoretical values with experimental data at 143 K is promising. Approximations to increase the computational efficiency are proposed.
Thibault
Franck
F
Institut de Physique de Rennes, UMR CNRS 6251, Université de Rennes I, F-35042, Rennes, France. Franck.Thibault@univ-rennes1.fr
Corretja
Benoît
B
Viel
Alexandra
A
Bermejo
Dionisio
D
Martínez
Raúl Z
RZ
Bussery-Honvault
Béatrice
B