Dissociation of H2 molecule on the {\beta}-Ga2O3 (100)B surface: The   critical role of oxygen vacancy
  We systematically study the dissociation of H2 molecules on the {\beta}-Ga2O3 (100)B surface, with the influences of surface oxygen vacancy being considered. After introducing the surface oxygen vacancy, the nearest topmost O(I) atom becomes very active, and hydrogen molecules become much easier to dissociate. 
Yu Yang, Ping Zhang
cond-mat.mtrl-sci