DOI: 10.17188/1203833
title: Materials Data on Zn4As2O9 by Materials Project

description: Zn4As2O9 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are four inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to five O2- atoms to form distorted ZnO5 trigonal bipyramids that share corners with four AsO4 tetrahedra, corners with two equivalent ZnO5 trigonal bipyramids, corners with three equivalent ZnO4 trigonal pyramids, and an edgeedge with one ZnO6 octahedra. There are a spread of Zn–O bond distances ranging from 1.97–2.18 Å. In the second Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 trigonal pyramids that share corners with two AsO4 tetrahedra, corners with four ZnO5 trigonal bipyramids, an edgeedge with one ZnO5 trigonal bipyramid, and an edgeedge with one ZnO4 trigonal pyramid. There are three shorter (1.96 Å) and one longer (2.11 Å) Zn–O bond lengths. In the third Zn2+ site, Zn2+ is bonded to six O2- atoms to form distorted ZnO6 octahedra that share corners with six AsO4 tetrahedra, an edgeedge with one ZnO6 octahedra, and edges with two ZnO5 trigonal bipyramids. There are a spread of Zn–O bond distances ranging from 2.05–2.35 Å. In the fourth Zn2+ site, Zn2+ is bonded to five O2- atoms to form ZnO5 trigonal bipyramids that share corners with four AsO4 tetrahedra, corners with two equivalent ZnO5 trigonal bipyramids, a cornercorner with one ZnO4 trigonal pyramid, an edgeedge with one ZnO6 octahedra, and an edgeedge with one ZnO4 trigonal pyramid. There are a spread of Zn–O bond distances ranging from 2.03–2.20 Å. There are two inequivalent As5+ sites. In the first As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with four equivalent ZnO6 octahedra, corners with three ZnO5 trigonal bipyramids, and a cornercorner with one ZnO4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 40–58°. There is two shorter (1.72 Å) and two longer (1.73 Å) As–O bond length. In the second As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with two equivalent ZnO6 octahedra, corners with five ZnO5 trigonal bipyramids, and a cornercorner with one ZnO4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 63–67°. There are a spread of As–O bond distances ranging from 1.72–1.76 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded to four Zn2+ atoms to form distorted edge-sharing OZn4 trigonal pyramids. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Zn2+ and one As5+ atom. In the third O2- site, O2- is bonded in a trigonal planar geometry to two Zn2+ and one As5+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Zn2+ and one As5+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two Zn2+ and one As5+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Zn2+ and one As5+ atom. In the seventh O2- site, O2- is bonded in a trigonal planar geometry to two Zn2+ and one As5+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to two Zn2+ and one As5+ atom. In the ninth O2- site, O2- is bonded in a trigonal non-coplanar geometry to two Zn2+ and one As5+ atom.