Natural Science Forum / Physics / Research / July 2009

i have heard the commercial package gaussian does some atomic
and molecular dynamics using semi-classical methods. not a full
quantum mechanical scattering treatment, although the molecular
structure calculation in gaussian are fully quantum mechanical.

There are some groups concerned with reactive scattering of three to five
atom systems. These systems can be investigated with full quantitative
quantum mechanical treatments of all relevant physical effects of both the
electronic structure and the reactive scattering itself.

Some pointers on recent work in this direction:

Hu,Schaty, Theories of reactive scattering, J. Chem. Phys. 125, 132301
(2006); DOI:10.1063/1.2213961

Che et al, Breakdown of the Born-Oppenheimer Approximation in the F +
o-D2 -> DF + D Reaction, Science 317, 1061 (2007),
DOI:10.1126/science.1144984

De Fazio et al - Exact state-to-state quantum dynamics of the
F+HD-->HF(v[prime]=2)+D reaction on model potential energy surfaces, J.
Chem. Phys. 129, 064303 (2008); DOI:10.1063/1.2964103

Wu, Werner, Manthe - First-Principles Theory for the H + CH4 -> H2 + CH3
Reaction, Science 306, 2227 (2004), DOI:10.1126/science.1104085

etc. You can find much more in this direction by following the citations of
the potential energy surface articles in Google Scholars or other cross
references in the articles.

Typically several programs need to be applied, and these kinds of
simulations are not routine tasks. You'd need a program which is able to do
good Multireference CI treatments for electronic potential energy surfaces
(e.g., MOLPRO), something to calculate and parameterize the PES based on
that, and another one to do the actual scattering simulations.