Materials Data on Mg2Nb3Bi3O14 by Materials Project
Mg2Nb3Bi3O14 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a distorted linear geometry to eight O2- atoms. There are two shorter (1.97 Å) and six longer (2.67 Å) Mg–O bond lengths. In the second Mg2+ site, Mg2+ is bonded to six equivalent O2- atoms to form MgO6 octahedra that share corners with six equivalent NbO6 octahedra. The corner-sharing octahedral tilt angles are 53°. All Mg–O bond lengths are 2.12 Å. Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two equivalent MgO6 octahedra and corners with four equivalent NbO6 octahedra. The corner-sharing octahedra tilt angles range from 42–53°. There are two shorter (1.98 Å) and four longer (2.02 Å) Nb–O bond lengths. Bi3+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Bi–O bond distances ranging from 2.39–2.62 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to one Mg2+ and three equivalent Bi3+ atoms to form distorted corner-sharing OMgBi3 tetrahedra. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Mg2+, two equivalent Nb5+, and one Bi3+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Mg2+, one Nb5+, and two equivalent Bi3+ atoms.