Materials Data on Bi2Se2S by Materials Project
Bi2Se2S crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded in a 7-coordinate geometry to four Se2- and three equivalent S2- atoms. There are a spread of Bi–Se bond distances ranging from 2.90–3.54 Å. There are two shorter (2.71 Å) and one longer (2.98 Å) Bi–S bond lengths. In the second Bi3+ site, Bi3+ is bonded to five Se2- atoms to form distorted edge-sharing BiSe5 square pyramids. There are a spread of Bi–Se bond distances ranging from 2.75–3.11 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to five Bi3+ atoms to form distorted edge-sharing SeBi5 square pyramids. In the second Se2- site, Se2- is bonded in a 3-coordinate geometry to four Bi3+ atoms. S2- is bonded in a 3-coordinate geometry to three equivalent Bi3+ atoms.