Materials Data on Er3GaNiS7 by Materials Project

Abstract

Er3NiGaS7 crystallizes in the hexagonal P6_3 space group. The structure is three-dimensional. Er3+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of Er–S bond distances ranging from 2.72–2.99 Å. Ni2+ is bonded to six equivalent S2- atoms to form face-sharing NiS6 octahedra. There are three shorter (2.41 Å) and three longer (2.52 Å) Ni–S bond lengths. Ga3+ is bonded in a tetrahedral geometry to four S2- atoms. There are one shorter (2.26 Å) and three longer (2.28 Å) Ga–S bond lengths. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent Er3+ and one Ga3+ atom. In the second S2- site, S2- is bonded to three equivalent Er3+ and one Ga3+ atom to form distorted corner-sharing SEr3Ga tetrahedra. In the third S2- site, S2- is bonded to three equivalent Er3+ and two equivalent Ni2+ atoms to form distorted SEr3Ni2 square pyramids that share corners with two equivalent SEr3Ni2 square pyramids, corners with three equivalent SEr3Ga tetrahedra, edges with four equivalent SEr3Ni2 square pyramids, and faces with two equivalent SEr3Ni2 square pyramids.