The role of water in the thermal decomposition of HXeCl in the HXeCl-H2O complex: spectator or chemical participant?

Abstract

The role of water in chemical reactions is of fundamental importance across many areas of research. Here we investigate the role of water for the thermal decomposition of the noble-gas hydride HXeCl in the HXeCl-H/D2O complex. The study was carried out via ab initio calculations and Ab Initio Molecular Dynamics (AIMD) simulations. Results of the calculations for the isolated complex are compared with previous experiments carried out for the complex in a Xe matrix. The simulations show that the deuteration of water has a major effect on the reaction outcome, transforming the role of water essentially into that of a mere spectator, as was seen experimentally. When the simulations include H2O rather than D2O, a large fraction of the trajectories show H-exchange reaction between water and HXeCl during its decomposition process. This predicts a dramatic H/D isotopic effect on the role of water in the decomposition. Effects of a Xe matrix on the above dynamics were explored via a simplistic continuum model of the environment for which, the results were about the same. It is concluded that a simple model of an isolated complex can be useful for the analysis of corresponding processes in inert host matrices and clusters.

Abstract as supplied by the indexing source. © the authors / publisher.