It was found that several Ti-H complexes were generated in crystalline samples by means of wet chemical etching or remote H-plasma treatments. Two electrically active (Ec - 0.3leV, Ec - 0.57eV), and one electrically inactive, Ti-H complexes were identified. The passive Ti-H complex dissociated at temperatures above 570K; thus leading to an increase in the interstitial Ti concentration.

W.Jost, J.Weber: Physical Review B, 1996, 54[16], R11038