Materials Data on NaSe2 by Materials Project
NaSe2 crystallizes in the tetragonal I-42d space group. The structure is three-dimensional. there are two inequivalent Na sites. In the first Na site, Na is bonded to six Se atoms to form distorted corner-sharing NaSe6 pentagonal pyramids. There are a spread of Na–Se bond distances ranging from 2.96–3.24 Å. In the second Na site, Na is bonded in a 6-coordinate geometry to six Se atoms. There are a spread of Na–Se bond distances ranging from 2.97–3.27 Å. There are two inequivalent Se sites. In the first Se site, Se is bonded in a distorted see-saw-like geometry to two Na and two Se atoms. There are one shorter (2.39 Å) and one longer (2.41 Å) Se–Se bond lengths. In the second Se site, Se is bonded in a 5-coordinate geometry to four Na and one Se atom.