Collision-induced Dissociation of Molecular Hydrogen at Low Densities
P. G. Martin, W. J. Keogh, M. E. Mandy;
ApJ, 1998, 499, 793
ABSTRACT:Quasi-classical trajectory studies have been carried out on a chemically accurate H4 potential-energy surface for H2 + H2 interactions to
obtain cross sections for collision-induced dissociation (CID) from the
H2(0, 0) ground vibration-rotation state.
This is an important channel for
dissociation, particularly in a low-density gas.
These results are compared with
corresponding calculations for the H + H2 and He + H2 systems.
Collisions with the
H2(0, 0) collision partner do not show the same dynamical elevation of
threshold for CID seen previously for collisions with He.
Despite the energetic
threshold, H2(0, 0) is a much less effective collision partner in promoting CID
than is H.
Thermal rate coefficients for CID from the ground state are
evaluated and compared to earlier approximations.
A comparison with electron
impact dissociation is also made.
KEYWORDS: ism: molecules, molecular data, molecular processes
PERSOKEY:general ism, h2, ,
CODE: martin98