Materials Data on Ag2BiSbSe4 by Materials Project
Ag2BiSbSe4 is alpha Po-derived structured and crystallizes in the tetragonal I-4m2 space group. The structure is three-dimensional. there are two inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded to six Se2- atoms to form AgSe6 octahedra that share corners with two equivalent SbSe6 octahedra, corners with four equivalent AgSe6 octahedra, edges with four equivalent AgSe6 octahedra, edges with four equivalent BiSe6 octahedra, and edges with four equivalent SbSe6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are four shorter (2.92 Å) and two longer (2.99 Å) Ag–Se bond lengths. In the second Ag1+ site, Ag1+ is bonded to six Se2- atoms to form AgSe6 octahedra that share corners with two equivalent BiSe6 octahedra, corners with four equivalent AgSe6 octahedra, edges with four equivalent AgSe6 octahedra, edges with four equivalent BiSe6 octahedra, and edges with four equivalent SbSe6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are two shorter (2.91 Å) and four longer (2.92 Å) Ag–Se bond lengths. Bi3+ is bonded to six Se2- atoms to form BiSe6 octahedra that share corners with two equivalent AgSe6 octahedra, corners with four equivalent BiSe6 octahedra, edges with four equivalent SbSe6 octahedra, and edges with eight AgSe6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are four shorter (2.92 Å) and two longer (2.96 Å) Bi–Se bond lengths. Sb3+ is bonded to six Se2- atoms to form SbSe6 octahedra that share corners with two equivalent AgSe6 octahedra, corners with four equivalent SbSe6 octahedra, edges with four equivalent BiSe6 octahedra, and edges with eight AgSe6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are two shorter (2.87 Å) and four longer (2.92 Å) Sb–Se bond lengths. There are six inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to three Ag1+, one Bi3+, and two equivalent Sb3+ atoms to form SeAg3BiSb2 octahedra that share corners with six SeAg3BiSb2 octahedra and edges with twelve SeAg3Bi2Sb octahedra. The corner-sharing octahedra tilt angles range from 0–1°. Both Se–Ag bond lengths are 2.92 Å. The Se–Bi bond length is 2.96 Å. Both Se–Sb bond lengths are 2.92 Å. In the second Se2- site, Se2- is bonded to three Ag1+, two equivalent Bi3+, and one Sb3+ atom to form SeAg3Bi2Sb octahedra that share corners with six SeAg3Bi2Sb octahedra and edges with twelve SeAg3BiSb2 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the third Se2- site, Se2- is bonded to three Ag1+, one Bi3+, and two equivalent Sb3+ atoms to form SeAg3BiSb2 octahedra that share corners with six SeAg3BiSb2 octahedra and edges with twelve SeAg3Bi2Sb octahedra. The corner-sharing octahedra tilt angles range from 0–1°. The Se–Bi bond length is 2.96 Å. In the fourth Se2- site, Se2- is bonded to three Ag1+, two equivalent Bi3+, and one Sb3+ atom to form SeAg3Bi2Sb octahedra that share corners with six SeAg3Bi2Sb octahedra and edges with twelve SeAg3BiSb2 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the fifth Se2- site, Se2- is bonded to three Ag1+, one Bi3+, and two equivalent Sb3+ atoms to form SeAg3BiSb2 octahedra that share corners with six SeAg3BiSb2 octahedra and edges with twelve SeAg3Bi2Sb octahedra. The corner-sharing octahedra tilt angles range from 0–1°. The Se–Ag bond length is 2.91 Å. In the sixth Se2- site, Se2- is bonded to three Ag1+, one Bi3+, and two equivalent Sb3+ atoms to form a mixture of corner and edge-sharing SeAg3BiSb2 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are one shorter (2.91 Å) and two longer (2.92 Å) Se–Ag bond lengths. Both Se–Sb bond lengths are 2.92 Å.