DOI: 10.17188/1191164
title: Materials Data on Na2Ga2As3 by Materials Project

description: Na2Ga2As3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six As+2.67- atoms to form NaAs6 octahedra that share corners with eight GaAs4 tetrahedra, a cornercorner with one NaAs5 trigonal bipyramid, an edgeedge with one NaAs6 octahedra, edges with four GaAs4 tetrahedra, and an edgeedge with one NaAs5 trigonal bipyramid. There are a spread of Na–As bond distances ranging from 3.05–3.25 Å. In the second Na1+ site, Na1+ is bonded to five As+2.67- atoms to form distorted NaAs5 trigonal bipyramids that share a cornercorner with one NaAs6 octahedra, corners with six GaAs4 tetrahedra, an edgeedge with one NaAs6 octahedra, edges with four GaAs4 tetrahedra, and an edgeedge with one NaAs5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 84°. There are a spread of Na–As bond distances ranging from 3.02–3.23 Å. In the third Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five As+2.67- atoms. There are a spread of Na–As bond distances ranging from 3.08–3.34 Å. In the fourth Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five As+2.67- atoms. There are a spread of Na–As bond distances ranging from 2.90–3.34 Å. There are four inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four As+2.67- atoms to form GaAs4 tetrahedra that share a cornercorner with one NaAs6 octahedra, corners with five GaAs4 tetrahedra, corners with two equivalent NaAs5 trigonal bipyramids, an edgeedge with one NaAs6 octahedra, an edgeedge with one GaAs4 tetrahedra, and an edgeedge with one NaAs5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 21°. There are a spread of Ga–As bond distances ranging from 2.47–2.63 Å. In the second Ga3+ site, Ga3+ is bonded to four As+2.67- atoms to form GaAs4 tetrahedra that share corners with two equivalent NaAs6 octahedra, corners with five GaAs4 tetrahedra, a cornercorner with one NaAs5 trigonal bipyramid, edges with two equivalent NaAs6 octahedra, and an edgeedge with one GaAs4 tetrahedra. The corner-sharing octahedra tilt angles range from 25–60°. There are a spread of Ga–As bond distances ranging from 2.50–2.54 Å. In the third Ga3+ site, Ga3+ is bonded to four As+2.67- atoms to form GaAs4 tetrahedra that share corners with three equivalent NaAs6 octahedra, corners with five GaAs4 tetrahedra, a cornercorner with one NaAs5 trigonal bipyramid, an edgeedge with one NaAs6 octahedra, an edgeedge with one GaAs4 tetrahedra, and an edgeedge with one NaAs5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 5–55°. There are a spread of Ga–As bond distances ranging from 2.48–2.58 Å. In the fourth Ga3+ site, Ga3+ is bonded to four As+2.67- atoms to form GaAs4 tetrahedra that share corners with two equivalent NaAs6 octahedra, corners with five GaAs4 tetrahedra, corners with two equivalent NaAs5 trigonal bipyramids, an edgeedge with one GaAs4 tetrahedra, and edges with two equivalent NaAs5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 29–34°. There are a spread of Ga–As bond distances ranging from 2.51–2.57 Å. There are six inequivalent As+2.67- sites. In the first As+2.67- site, As+2.67- is bonded in a 6-coordinate geometry to three Na1+ and three Ga3+ atoms. In the second As+2.67- site, As+2.67- is bonded to four Na1+ and three Ga3+ atoms to form edge-sharing AsNa4Ga3 pentagonal bipyramids. In the third As+2.67- site, As+2.67- is bonded to four Na1+ and three Ga3+ atoms to form distorted edge-sharing AsNa4Ga3 pentagonal bipyramids. In the fourth As+2.67- site, As+2.67- is bonded in a 7-coordinate geometry to four Na1+, two Ga3+, and one As+2.67- atom. The As–As bond length is 2.51 Å. In the fifth As+2.67- site, As+2.67- is bonded in a 6-coordinate geometry to three Na1+ and three Ga3+ atoms. In the sixth As+2.67- site, As+2.67- is bonded in a 6-coordinate geometry to three Na1+, two Ga3+, and one As+2.67- atom.