Materials Data on MgTi3Nb2(PbO3)6 by Materials Project

Abstract

MgTi3Nb2(PbO3)6 is (Cubic) Perovskite-derived structured and crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Mg2+ is bonded to six equivalent O2- atoms to form MgO6 octahedra that share corners with six equivalent NbO6 octahedra and faces with eight PbO12 cuboctahedra. The corner-sharing octahedral tilt angles are 3°. All Mg–O bond lengths are 2.06 Å. There are two inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with three equivalent TiO6 octahedra, corners with three equivalent NbO6 octahedra, and faces with eight PbO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–2°. There is three shorter (1.98 Å) and three longer (2.00 Å) Ti–O bond length. In the second Ti4+ site, Ti4+ is bonded to six equivalent O2- atoms to form TiO6 octahedra that share corners with six equivalent TiO6 octahedra and faces with eight PbO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Ti–O bond lengths are 2.00 Å. Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with three equivalent MgO6 octahedra, corners with three equivalent TiO6 octahedra, and faces with eight PbO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 2–3°. There are three shorter (1.94 Å) and three longer (2.10 Å) Nb–O bond lengths. There are three inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded to twelve O2- atoms to form PbO12 cuboctahedra that share corners with twelve PbO12 cuboctahedra, faces with six PbO12 cuboctahedra, a faceface with one MgO6 octahedra, faces with three equivalent NbO6 octahedra, and faces with four TiO6 octahedra. All Pb–O bond lengths are 2.84 Å. In the second Pb2+ site, Pb2+ is bonded to twelve O2- atoms to form PbO12 cuboctahedra that share corners with twelve PbO12 cuboctahedra, faces with six PbO12 cuboctahedra, a faceface with one NbO6 octahedra, and faces with seven TiO6 octahedra. There are three shorter (2.80 Å) and nine longer (2.84 Å) Pb–O bond lengths. In the third Pb2+ site, Pb2+ is bonded to twelve O2- atoms to form PbO12 cuboctahedra that share corners with twelve PbO12 cuboctahedra, faces with six PbO12 cuboctahedra, a faceface with one TiO6 octahedra, faces with three equivalent MgO6 octahedra, and faces with four equivalent NbO6 octahedra. There are a spread of Pb–O bond distances ranging from 2.84–2.90 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to two Ti4+ and four Pb2+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to one Ti4+, one Nb5+, and four Pb2+ atoms. In the third O2- site, O2- is bonded in a linear geometry to one Mg2+, one Nb5+, and four Pb2+ atoms.