Photodissociation of HBr in and on Arn Clusters: The Role of the Position of the Molecule

0181679 - UFCH-W 20030106 RIV GB eng J - Článek v odborném periodiku
Nahler, N. H. - Baumfalk, R. - Buck, U. - Vach, H. - Slavíček, Petr - Jungwirth, Pavel
Photodissociation of HBr in and on Arn Clusters: The Role of the Position of the Molecule.
Physical Chemistry Chemical Physics. Roč. 5, - (2003), s. 3394-3401. ISSN 1463-9076. E-ISSN 1463-9084
Grant CEP: GA MŠMT LN00A032
Výzkumný záměr: CEZ:AV0Z4040901
Klíčová slova: HBr * photodissociation * Arn clusters
Kód oboru RIV: CF - Fyzikální chemie a teoretická chemie
Impakt faktor: 1.959, rok: 2003

Photodissociation experiments are carried out for single HBr molecules which areembedded in the interior or absorbed on the surface of large Ar$_n$ clusters.For the embedded case the size dependence is measured for the average sizesn=51, 139, 230, 290, and 450. For the surface case and the average sizen=139 the cluster temperature is varied by changing the source temperature fromT=163 K to 263 K. The measured kinetic energy of the H atom fragments is measuredexhibiting peaks at zero and 1.3 eV which mark completely caged and unperturbedfragments, respectively. The results are compared with Molecular Dynamics simulationswhich account for the quantum librational delocalization of the HBr molecule. The location of the molecule in/on the cluster is obtained from a trajectory study of the pick-upprocess under realistic conditions. For the embedded case corresponding to aco-expansion experiment, three argon layers are sufficient to completely hinderthe H atom.
Trvalý link: http://hdl.handle.net/11104/0078213