Two H-related defects in ZnO were identified by a combination of local vibrational mode spectroscopy and first-principles theory. The H-I center consisted of one H atom at the bond-center site oriented along the c axis of the crystal. The H-II center contains 2 non-equivalent H atoms primarily bound to O atoms. The polarized absorption data permitted the identification of H-II as being a Zn vacancy having two H atoms.

Hydrogen-Related Defects in ZnO Studied by Infrared Absorption Spectroscopy. Lavrov, E.V., Weber, J., Börrnert, F., Van de Walle, C.G., Helbig, R.: Physical Review B, 2002, 66[16], 165205