Materials Data on Ti2NiS4 by Materials Project
NiTi2S4 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Ti3+ is bonded to six S2- atoms to form TiS6 octahedra that share corners with six equivalent NiS6 octahedra, edges with six equivalent TiS6 octahedra, and a faceface with one NiS6 octahedra. The corner-sharing octahedra tilt angles range from 47–49°. There are a spread of Ti–S bond distances ranging from 2.42–2.48 Å. Ni2+ is bonded to six S2- atoms to form NiS6 octahedra that share corners with twelve equivalent TiS6 octahedra, edges with two equivalent NiS6 octahedra, and faces with two equivalent TiS6 octahedra. The corner-sharing octahedra tilt angles range from 47–49°. There are two shorter (2.35 Å) and four longer (2.40 Å) Ni–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a rectangular see-saw-like geometry to three equivalent Ti3+ and one Ni2+ atom. In the second S2- site, S2- is bonded to three equivalent Ti3+ and two equivalent Ni2+ atoms to form a mixture of distorted edge and corner-sharing STi3Ni2 square pyramids.