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, Zr O2, Hf O2, La2 O3, LaAl O3, Sn O2, Ti O2, SrTi O3, PbTi O3, and Sr Bi2 Ta2 O9, but deep in MgO, Al2 O3, Si O2, ZrSi O4, HfSi O4, and SrZr O3. It is borderline in SrO. The predictions are found to agree well with the experimental behavior of muonium in these oxides. © 2007 American Institute of Physics.