Materials Data on Al2Zn2S5 by Materials Project

Abstract

Zn2Al2S5 crystallizes in the hexagonal P6_3/mmc space group. The structure is two-dimensional and consists of two Zn2Al2S5 sheets oriented in the (0, 0, 1) direction. Zn2+ is bonded to six S2- atoms to form ZnS6 octahedra that share corners with six equivalent ZnS6 octahedra, corners with three equivalent AlS4 tetrahedra, edges with six equivalent ZnS6 octahedra, and a faceface with one ZnS6 octahedra. The corner-sharing octahedral tilt angles are 48°. There are three shorter (2.48 Å) and three longer (2.60 Å) Zn–S bond lengths. Al3+ is bonded to four S2- atoms to form AlS4 tetrahedra that share corners with three equivalent ZnS6 octahedra and corners with six equivalent AlS4 tetrahedra. The corner-sharing octahedral tilt angles are 59°. There are one shorter (2.18 Å) and three longer (2.34 Å) Al–S bond lengths. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a 6-coordinate geometry to six equivalent Zn2+ atoms. In the second S2- site, S2- is bonded to three equivalent Zn2+ and one Al3+ atom to form distorted corner-sharing SAlZn3 trigonal pyramids. In the third S2- site, S2- is bonded in a trigonal non-coplanar geometry to three equivalent Al3+ atoms.