Materials Data on TiH2 by Materials Project

TiH2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Ti2+ is bonded in a 9-coordinate geometry to nine H1- atoms. There are a spread of Ti–H bond distances ranging from 1.90–2.10 Å. There are two inequivalent H1- sites. In the first H1- site, H1- is bonded to four equivalent Ti2+ atoms to form HTi4 tetrahedra that share corners with twelve equivalent HTi5 square pyramids, corners with four equivalent HTi4 tetrahedra, edges with four equivalent HTi5 square pyramids, and edges with four equivalent HTi4 tetrahedra. In the second H1- site, H1- is bonded to five equivalent Ti2+ atoms to form distorted HTi5 square pyramids that share corners with four equivalent HTi5 square pyramids, corners with twelve equivalent HTi4 tetrahedra, edges with eight equivalent HTi5 square pyramids, and edges with four equivalent HTi4 tetrahedra.