Adsorption of hydrogen on b-Ga2O3(100): a theoretical study

C. R. LUNA; E. GONZÁLEZ; P. JASEN; A. JUAN

SURFACE REVIEW AND LETTERS

World Scientific

Lugar: Singapore; Año: 2007 vol. 14 p. 79 - 86

0218-625X

We have modeled the (100) surface of b-Ga2O3 with a clear-cut optimization from ab-initio  calculations. The adsorption geometry of one hydrogen atom on this surface was determined by  a semi-empirical quantum chemistry method. H is found bonded to a tetrahedral Ga atom and  no bond with surface oxygen atoms is detected. As a consequence of this Ga–H bond, the Ga–O  overlap population decreases. This result is in good agreement with the recent spectroscopic  determination of Ga–H IR frequencies on supported catalysts. The orbital composition of the  Ga–H bond and density of states of tetrahedral and octahedral gallium ions, Ga(I), Ga(II), and  that of oxygen before and after H adsorption are also addressed.