Materials Data on NaTiSe4 by Materials Project
NaTiSe4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight Se+1.25- atoms. There are a spread of Na–Se bond distances ranging from 3.04–3.58 Å. In the second Na1+ site, Na1+ is bonded in a 7-coordinate geometry to seven Se+1.25- atoms. There are a spread of Na–Se bond distances ranging from 2.99–3.43 Å. There are two inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to seven Se+1.25- atoms to form distorted face-sharing TiSe7 pentagonal bipyramids. There are a spread of Ti–Se bond distances ranging from 2.40–2.86 Å. In the second Ti4+ site, Ti4+ is bonded to seven Se+1.25- atoms to form face-sharing TiSe7 pentagonal bipyramids. There are a spread of Ti–Se bond distances ranging from 2.45–2.79 Å. There are eight inequivalent Se+1.25- sites. In the first Se+1.25- site, Se+1.25- is bonded in a 3-coordinate geometry to two equivalent Na1+, one Ti4+, and one Se+1.25- atom. The Se–Se bond length is 2.41 Å. In the second Se+1.25- site, Se+1.25- is bonded in a 5-coordinate geometry to two Na1+, two Ti4+, and one Se+1.25- atom. In the third Se+1.25- site, Se+1.25- is bonded in a 4-coordinate geometry to two equivalent Na1+ and two Ti4+ atoms. In the fourth Se+1.25- site, Se+1.25- is bonded in a 2-coordinate geometry to one Na1+ and two Ti4+ atoms. In the fifth Se+1.25- site, Se+1.25- is bonded to three Na1+ and two Ti4+ atoms to form distorted edge-sharing SeNa3Ti2 square pyramids. In the sixth Se+1.25- site, Se+1.25- is bonded in a 4-coordinate geometry to two equivalent Na1+ and two Ti4+ atoms. In the seventh Se+1.25- site, Se+1.25- is bonded in a 2-coordinate geometry to one Na1+ and two Ti4+ atoms. In the eighth Se+1.25- site, Se+1.25- is bonded in a 2-coordinate geometry to two equivalent Na1+ and one Ti4+ atom.