Institut für Physikalische und Theoretische Chemie
Keywords: molecular dynamics, quantum dynamics, photodissociation, photoassociation, photochemistry
Computer simulations of molecular dynamics are performed with the help of mixed quantum/classical methods. These techniques allow the fully quantum-mechanical treatment of a small system (usually one or two light particles) in the presence of a large number of heavy particles which are modeled as classical particles. Naturally these methods are most suited for the theoretical treatment of spectroscopy and/or photochemistry of small molecules in solution. There the most important quantum effects are mainly localized in the solute molecule. The most important solvent effects are shifts and/or splittings of spectroscopic lines or promotion or hindering of reactions by collisions with the solvent particles, respectively. Model systems currently under investigation are the following: (1) Photodissociation of hydrogen halide guest molecules in clusters and in matrices of rare gas atoms. (2) Electron transfer in aromatic double molecules in the gas phase and in solution. (3) (Photo-)Association of small molecules in the gas phase and in rare gas environment.