Materials Data on KAlSe2 by Materials Project
KAlSe2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of K–Se bond distances ranging from 3.42–3.98 Å. In the second K1+ site, K1+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of K–Se bond distances ranging from 3.34–3.97 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four Se2- atoms to form corner-sharing AlSe4 tetrahedra. There are a spread of Al–Se bond distances ranging from 2.41–2.43 Å. In the second Al3+ site, Al3+ is bonded to four Se2- atoms to form corner-sharing AlSe4 tetrahedra. There are a spread of Al–Se bond distances ranging from 2.40–2.44 Å. There are five inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted water-like geometry to four K1+ and two Al3+ atoms. In the second Se2- site, Se2- is bonded in a 2-coordinate geometry to four K1+ and two Al3+ atoms. In the third Se2- site, Se2- is bonded in a distorted water-like geometry to four K1+ and two equivalent Al3+ atoms. In the fourth Se2- site, Se2- is bonded in a 2-coordinate geometry to four K1+ and two Al3+ atoms. In the fifth Se2- site, Se2- is bonded in a distorted water-like geometry to four K1+ and two equivalent Al3+ atoms.