DOI: 10.17188/1191165
title: Materials Data on K2Ga2As3 by Materials Project

description: K2Ga2As3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to six As+2.67- atoms to form distorted KAs6 octahedra that share corners with eight GaAs4 tetrahedra, an edgeedge with one KAs6 octahedra, and edges with four GaAs4 tetrahedra. There are a spread of K–As bond distances ranging from 3.31–3.71 Å. In the second K1+ site, K1+ is bonded in a 6-coordinate geometry to six As+2.67- atoms. There are a spread of K–As bond distances ranging from 3.28–3.81 Å. In the third K1+ site, K1+ is bonded in a 5-coordinate geometry to five As+2.67- atoms. There are a spread of K–As bond distances ranging from 3.40–3.63 Å. In the fourth K1+ site, K1+ is bonded in a 2-coordinate geometry to six As+2.67- atoms. There are a spread of K–As bond distances ranging from 3.19–3.89 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 KAs6 octahedra, corners with five GaAs4 tetrahedra, an edgeedge with one KAs6 octahedra, and an edgeedge with one GaAs4 tetrahedra. The corner-sharing octahedral tilt angles are 17°. There are a spread of Ga–As bond distances ranging from 2.49–2.65 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 KAs6 octahedra, corners with five GaAs4 tetrahedra, edges with two equivalent KAs6 octahedra, and an edgeedge with one GaAs4 tetrahedra. The corner-sharing octahedra tilt angles range from 28–63°. There are a spread of Ga–As bond distances ranging from 2.53–2.55 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 KAs6 octahedra, corners with five GaAs4 tetrahedra, an edgeedge with one KAs6 octahedra, and an edgeedge with one GaAs4 tetrahedra. The corner-sharing octahedra tilt angles range from 1–55°. There are a spread of Ga–As bond distances ranging from 2.49–2.56 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 KAs6 octahedra, corners with five GaAs4 tetrahedra, and an edgeedge with one GaAs4 tetrahedra. The corner-sharing octahedra tilt angles range from 28–29°. There are a spread of Ga–As bond distances ranging from 2.55–2.60 Å. There are six inequivalent As+2.67- sites. In the first As+2.67- site, As+2.67- is bonded in a 3-coordinate geometry to three K1+ and three Ga3+ atoms. In the second As+2.67- site, As+2.67- is bonded to four K1+ and three Ga3+ atoms to form distorted edge-sharing AsK4Ga3 pentagonal bipyramids. In the third As+2.67- site, As+2.67- is bonded in a 6-coordinate geometry to three K1+ and three Ga3+ atoms. In the fourth As+2.67- site, As+2.67- is bonded in a 7-coordinate geometry to four K1+, 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 3-coordinate geometry to five K1+ and three Ga3+ atoms. In the sixth As+2.67- site, As+2.67- is bonded in a 7-coordinate geometry to four K1+, two Ga3+, and one As+2.67- atom.