Materials Data on Na7I2O5 by Materials Project
Na7O5I2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. there are three inequivalent Na sites. In the first Na site, Na is bonded in a 5-coordinate geometry to five O and one I atom. There are four shorter (2.18 Å) and one longer (2.45 Å) Na–O bond lengths. The Na–I bond length is 3.23 Å. In the second Na site, Na is bonded in a 4-coordinate geometry to four equivalent O and two equivalent I atoms. All Na–O bond lengths are 2.46 Å. Both Na–I bond lengths are 3.47 Å. In the third Na site, Na is bonded in a 6-coordinate geometry to three O and three I atoms. There are one shorter (2.34 Å) and two longer (2.42 Å) Na–O bond lengths. There are one shorter (3.30 Å) and two longer (3.40 Å) Na–I bond lengths. There are two inequivalent O sites. In the first O site, O is bonded to five Na atoms to form face-sharing ONa5 square pyramids. In the second O site, O is bonded to five Na atoms to form a mixture of face and corner-sharing ONa5 square pyramids. There are two inequivalent I sites. In the first I site, I is bonded in a body-centered cubic geometry to eight equivalent Na atoms. In the second I site, I is bonded in a 9-coordinate geometry to nine Na atoms.