Behavior of hydrogen in wide band gap oxides

Abstract

The energy levels of interstitial hydrogen in various wide band gap oxides are calculated using a density function based method that does not need a band gap correction. The positive charge state has a large stabilization energy due to the formation of an O–H bond. The hydrogen level is found to be shallow in CdO, ZrO2, HfO2, La2O3, LaAlO3, SnO2, TiO2, SrTiO3, PbTiO3, and SrBi2Ta2O9, but deep in MgO, Al2O3, SiO2, ZrSiO4, HfSiO4, and SrZrO3. It is borderline in SrO. The predictions are found to agree well with the experimental behavior of muonium in these oxides.