Materials Data on TiNb(BiO3)3 by Materials Project
Bi3TiNbO9 crystallizes in the tetragonal I4mm space group. The structure is three-dimensional. Ti4+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ti–O bond distances ranging from 1.78–2.30 Å. Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles are 15°. There are a spread of Nb–O bond distances ranging from 1.92–2.25 Å. There are three inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded in a 4-coordinate geometry to eight O2- atoms. There are four shorter (2.32 Å) and four longer (2.88 Å) Bi–O bond lengths. In the second Bi3+ site, Bi3+ is bonded in a 4-coordinate geometry to eight O2- atoms. There are four shorter (2.30 Å) and four longer (2.90 Å) Bi–O bond lengths. In the third Bi3+ site, Bi3+ is bonded in a 12-coordinate geometry to twelve O2- atoms. There are a spread of Bi–O bond distances ranging from 2.49–3.03 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Ti4+ and four equivalent Bi3+ atoms. In the second O2- site, O2- is bonded in a single-bond geometry to one Nb5+ and four equivalent Bi3+ atoms. In the third O2- site, O2- is bonded in a distorted linear geometry to two equivalent Nb5+ and two equivalent Bi3+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ti4+ and two equivalent Bi3+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one Ti4+, one Nb5+, and four equivalent Bi3+ atoms. In the sixth O2- site, O2- is bonded to four Bi3+ atoms to form a mixture of corner and edge-sharing OBi4 tetrahedra.