Materials Data on BaAl4Se7 by Materials Project
BaAl4Se7 crystallizes in the monoclinic Pc space group. The structure is three-dimensional. Ba2+ is bonded in a 6-coordinate geometry to six Se2- atoms. There are a spread of Ba–Se bond distances ranging from 3.46–3.73 Å. There are four 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 2.37–2.47 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 2.38–2.50 Å. In the third 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 2.37–2.47 Å. In the fourth 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 2.38–2.50 Å. There are seven inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted water-like geometry to two equivalent Ba2+ and two Al3+ atoms. In the second Se2- site, Se2- is bonded in a 2-coordinate geometry to one Ba2+ and two Al3+ atoms. In the third Se2- site, Se2- is bonded in a distorted water-like geometry to one Ba2+ and two Al3+ atoms. In the fourth Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to three Al3+ atoms. In the fifth Se2- site, Se2- is bonded in a 2-coordinate geometry to one Ba2+ and two Al3+ atoms. In the sixth Se2- site, Se2- is bonded in a distorted water-like geometry to one Ba2+ and two Al3+ atoms. In the seventh Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to three Al3+ atoms.