Materials Data on Ti2NiP5 by Materials Project

Abstract

Ti2NiP5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Ti3+ sites. In the first Ti3+ site, Ti3+ is bonded to seven P+1.40- atoms to form distorted TiP7 pentagonal bipyramids that share corners with two equivalent PNiP3 tetrahedra, corners with four equivalent NiP5 trigonal bipyramids, edges with two equivalent NiP5 trigonal bipyramids, and faces with two equivalent TiP7 pentagonal bipyramids. There are a spread of Ti–P bond distances ranging from 2.50–2.63 Å. In the second Ti3+ site, Ti3+ is bonded in a 8-coordinate geometry to eight P+1.40- atoms. There are a spread of Ti–P bond distances ranging from 2.51–2.72 Å. Ni1+ is bonded to five P+1.40- atoms to form NiP5 trigonal bipyramids that share corners with four equivalent TiP7 pentagonal bipyramids, corners with two equivalent PNiP3 tetrahedra, edges with two equivalent TiP7 pentagonal bipyramids, and edges with two equivalent NiP5 trigonal bipyramids. There are a spread of Ni–P bond distances ranging from 2.17–2.32 Å. There are five inequivalent P+1.40- sites. In the first P+1.40- site, P+1.40- is bonded in a 8-coordinate geometry to four Ti3+ and four P+1.40- atoms. There are two shorter (2.41 Å) and two longer (2.55 Å) P–P bond lengths. In the second P+1.40- site, P+1.40- is bonded to four Ti3+ and two equivalent Ni1+ atoms to form distorted PTi4Ni2 pentagonal pyramids that share corners with two equivalent PNiP3 tetrahedra and faces with two equivalent PTi4Ni2 pentagonal pyramids. In the third P+1.40- site, P+1.40- is bonded in a 7-coordinate geometry to three Ti3+, two equivalent Ni1+, and two equivalent P+1.40- atoms. In the fourth P+1.40- site, P+1.40- is bonded in a 5-coordinate geometry to four Ti3+ and one P+1.40- atom. The P–P bond length is 2.20 Å. In the fifth P+1.40- site, P+1.40- is bonded to one Ni1+ and three P+1.40- atoms to form distorted PNiP3 tetrahedra that share corners with two equivalent TiP7 pentagonal bipyramids, corners with two equivalent PTi4Ni2 pentagonal pyramids, corners with two equivalent PNiP3 tetrahedra, and corners with two equivalent NiP5 trigonal bipyramids. Both P–P bond lengths are 2.22 Å.