Materials Data on Nb3(BiO3)5 by Materials Project
Bi5Nb3O15 crystallizes in the orthorhombic Pnc2 space group. The structure is two-dimensional and consists of one Nb(BiO2)4 sheet oriented in the (0, 0, 1) direction and one Nb2BiO7 sheet oriented in the (0, 0, 1) direction. In the Nb(BiO2)4 sheet, Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles are 31°. There are a spread of Nb–O bond distances ranging from 1.89–2.19 Å. There are two inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Bi–O bond distances ranging from 2.22–2.33 Å. In the second Bi3+ site, Bi3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Bi–O bond distances ranging from 2.28–2.81 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to four Bi3+ atoms to form a mixture of distorted corner and edge-sharing OBi4 tetrahedra. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Nb5+ and one Bi3+ atom. In the third O2- site, O2- is bonded to four Bi3+ atoms to form a mixture of distorted corner and edge-sharing OBi4 tetrahedra. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Nb5+ and two equivalent Bi3+ atoms. In the Nb2BiO7 sheet, Nb5+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Nb–O bond distances ranging from 1.81–2.41 Å. Bi3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Bi–O bond distances ranging from 2.16–2.96 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Nb5+ and one Bi3+ atom. In the second O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Nb5+ and three equivalent Bi3+ atoms. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Nb5+ and two equivalent Bi3+ atoms. In the fourth O2- site, O2- is bonded in a single-bond geometry to one Nb5+ atom.