Materials Data on NaB9Se8 by Materials Project
NaB9Se8 crystallizes in the trigonal P-3 space group. The structure is three-dimensional. Na1+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of Na–Se bond distances ranging from 3.13–3.65 Å. There are nine inequivalent B+1.67+ sites. In the first B+1.67+ site, B+1.67+ is bonded in a single-bond geometry to one Se2- atom. The B–Se bond length is 2.02 Å. In the second B+1.67+ site, B+1.67+ is bonded in a single-bond geometry to one Se2- atom. The B–Se bond length is 2.02 Å. In the third B+1.67+ site, B+1.67+ is bonded in a single-bond geometry to one Se2- atom. The B–Se bond length is 2.02 Å. In the fourth B+1.67+ site, B+1.67+ is bonded in a trigonal planar geometry to three Se2- atoms. There are a spread of B–Se bond distances ranging from 1.93–2.01 Å. In the fifth B+1.67+ site, B+1.67+ is bonded in a single-bond geometry to one Se2- atom. The B–Se bond length is 2.03 Å. In the sixth B+1.67+ site, B+1.67+ is bonded in a single-bond geometry to one Se2- atom. The B–Se bond length is 2.02 Å. In the seventh B+1.67+ site, B+1.67+ is bonded in a trigonal planar geometry to three Se2- atoms. There is two shorter (1.96 Å) and one longer (1.97 Å) B–Se bond length. In the eighth B+1.67+ site, B+1.67+ is bonded in a single-bond geometry to one Se2- atom. The B–Se bond length is 2.02 Å. In the ninth B+1.67+ site, B+1.67+ is bonded in a trigonal planar geometry to three Se2- atoms. There are a spread of B–Se bond distances ranging from 1.95–1.98 Å. There are eight inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted L-shaped geometry to two equivalent Na1+ and two B+1.67+ atoms. In the second Se2- site, Se2- is bonded in an L-shaped geometry to two B+1.67+ atoms. In the third Se2- site, Se2- is bonded in a distorted water-like geometry to one Na1+ and two B+1.67+ atoms. In the fourth Se2- site, Se2- is bonded in a distorted single-bond geometry to one B+1.67+ atom. In the fifth Se2- site, Se2- is bonded in a 2-coordinate geometry to one Na1+ and two B+1.67+ atoms. In the sixth Se2- site, Se2- is bonded in a 3-coordinate geometry to one Na1+ and two B+1.67+ atoms. In the seventh Se2- site, Se2- is bonded in a 3-coordinate geometry to one Na1+ and two B+1.67+ atoms. In the eighth Se2- site, Se2- is bonded in a 2-coordinate geometry to one Na1+ and two B+1.67+ atoms.