Materials Data on Pr4NiS7 by Materials Project

Pr4NiS7 crystallizes in the hexagonal P6_3 space group. The structure is three-dimensional. there are two inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded in a distorted rectangular see-saw-like geometry to four S2- atoms. There are one shorter (2.67 Å) and three longer (2.70 Å) Pr–S bond lengths. In the second Pr3+ site, Pr3+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of Pr–S bond distances ranging from 2.74–3.22 Å. Ni2+ is bonded to six equivalent S2- atoms to form face-sharing NiS6 octahedra. There are three shorter (2.44 Å) and three longer (2.70 Å) Ni–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 four Pr3+ atoms. In the second S2- site, S2- is bonded to four Pr3+ atoms to form corner-sharing SPr4 tetrahedra. In the third S2- site, S2- is bonded to three equivalent Pr3+ and two equivalent Ni2+ atoms to form distorted SPr3Ni2 square pyramids that share corners with two equivalent SPr3Ni2 square pyramids, corners with three equivalent SPr4 tetrahedra, edges with four equivalent SPr3Ni2 square pyramids, and faces with two equivalent SPr3Ni2 square pyramids.