Materials Data on NaTa4Bi5O18 by Materials Project
NaTa4Bi5O18 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.44–2.67 Å. There are two inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 24–29°. There are a spread of Ta–O bond distances ranging from 1.90–2.16 Å. In the second Ta5+ site, Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 23–29°. There are a spread of Ta–O bond distances ranging from 1.89–2.17 Å. There are three inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Bi–O bond distances ranging from 2.26–2.62 Å. In the second Bi3+ site, Bi3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Bi–O bond distances ranging from 2.22–2.64 Å. In the third Bi3+ site, Bi3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Bi–O bond distances ranging from 2.22–2.66 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, two equivalent Ta5+, and one Bi3+ atom. In the second O2- site, O2- is bonded in a distorted see-saw-like geometry to one Na1+, two equivalent Ta5+, and one Bi3+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one Ta5+ and two Bi3+ atoms. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to one Ta5+ and two Bi3+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to two Ta5+ and one Bi3+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+ and two Ta5+ atoms. In the seventh O2- site, O2- is bonded to four Bi3+ atoms to form a mixture of corner and edge-sharing OBi4 tetrahedra. In the eighth O2- site, O2- is bonded to four Bi3+ atoms to form a mixture of corner and edge-sharing OBi4 tetrahedra. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, two Ta5+, and one Bi3+ atom. In the tenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Na1+, two Ta5+, and one Bi3+ atom.