Na5Ti3O8 is Caswellsilverite-like structured and crystallizes in the trigonal R-3m space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NaO6 octahedra that share corners with six equivalent Ti(1)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with four equivalent Na(1)O6 octahedra, and edges with four equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-11°. In the second Na site, Na(2) is bonded to six equivalent O(2) atoms to form NaO6 octahedra that share corners with six equivalent Na(3)O6 octahedra, edges with six equivalent Na(1)O6 octahedra, and edges with six equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles are 16°. In the third Na site, Na(3) is bonded to six equivalent O(2) atoms to form distorted NaO6 octahedra that share corners with six equivalent Na(2)O6 octahedra, edges with six equivalent Na(1)O6 octahedra, and edges with six equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles are 16°. Ti(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form TiO6 octahedra that share corners with six equivalent Na(1)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with four equivalent Na(1)O6 octahedra, and edges with four equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-11°. There are two inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Na(1) and three equivalent Ti(1) atoms to form ONa3Ti3 octahedra that share corners with six equivalent O(1)Na3Ti3 octahedra and edges with twelve equivalent O(2)Na4Ti2 octahedra. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded to one Na(2), one Na(3), two equivalent Na(1), and two equivalent Ti(1) atoms to form ONa4Ti2 octahedra that share corners with six equivalent O(2)Na4Ti2 octahedra, edges with four equivalent O(1)Na3Ti3 octahedra, and edges with eight equivalent O(2)Na4Ti2 octahedra. The corner-sharing octahedra are not tilted.
Na5Ti3O8 is Caswellsilverite-like structured and crystallizes in the trigonal R-3m space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NaO6 octahedra that share corners with six equivalent Ti(1)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with four equivalent Na(1)O6 octahedra, and edges with four equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-11°. Both Na(1)-O(1) bond lengths are 2.38 Å. All Na(1)-O(2) bond lengths are 2.48 Å. In the second Na site, Na(2) is bonded to six equivalent O(2) atoms to form NaO6 octahedra that share corners with six equivalent Na(3)O6 octahedra, edges with six equivalent Na(1)O6 octahedra, and edges with six equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles are 16°. All Na(2)-O(2) bond lengths are 2.23 Å. In the third Na site, Na(3) is bonded to six equivalent O(2) atoms to form distorted NaO6 octahedra that share corners with six equivalent Na(2)O6 octahedra, edges with six equivalent Na(1)O6 octahedra, and edges with six equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles are 16°. All Na(3)-O(2) bond lengths are 2.29 Å. Ti(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form TiO6 octahedra that share corners with six equivalent Na(1)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with four equivalent Na(1)O6 octahedra, and edges with four equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-11°. Both Ti(1)-O(1) bond lengths are 2.10 Å. All Ti(1)-O(2) bond lengths are 2.02 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Na(1) and three equivalent Ti(1) atoms to form ONa3Ti3 octahedra that share corners with six equivalent O(1)Na3Ti3 octahedra and edges with twelve equivalent O(2)Na4Ti2 octahedra. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded to one Na(2), one Na(3), two equivalent Na(1), and two equivalent Ti(1) atoms to form ONa4Ti2 octahedra that share corners with six equivalent O(2)Na4Ti2 octahedra, edges with four equivalent O(1)Na3Ti3 octahedra, and edges with eight equivalent O(2)Na4Ti2 octahedra. The corner-sharing octahedra are not tilted.