Materials Data on RbMg14CO16 by Materials Project
RbMg14CO16 crystallizes in the orthorhombic Pmmm space group. The structure is three-dimensional. Rb1+ is bonded to six O2- atoms to form distorted RbO6 octahedra that share corners with two equivalent RbO6 octahedra, corners with two equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Rb–O bond distances ranging from 2.29–2.78 Å. There are eight inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent RbO6 octahedra, corners with four MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.02–2.29 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.02–2.29 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 octahedra that share corners with six MgO6 octahedra, edges with two equivalent RbO6 octahedra, and edges with eight MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–33°. There are a spread of Mg–O bond distances ranging from 1.97–2.39 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Mg–O bond distances ranging from 2.02–2.33 Å. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with two equivalent RbO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–10°. There are a spread of Mg–O bond distances ranging from 2.03–2.35 Å. In the sixth Mg2+ site, Mg2+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–14°. There are a spread of Mg–O bond distances ranging from 2.04–2.31 Å. In the seventh Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with two equivalent RbO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–10°. There are a spread of Mg–O bond distances ranging from 2.03–2.35 Å. In the eighth Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 octahedra that share corners with six equivalent MgO6 octahedra, an edgeedge with one RbO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 2–31°. There are a spread of Mg–O bond distances ranging from 2.00–2.61 Å. C3+ is bonded in a linear geometry to two equivalent O2- atoms. Both C–O bond lengths are 1.30 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded to one Rb1+ and five Mg2+ atoms to form ORbMg5 octahedra that share corners with four equivalent ORbMg5 octahedra, corners with two equivalent OMg5 square pyramids, and edges with ten OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–10°. In the second O2- site, O2- is bonded to five Mg2+ atoms to form OMg5 square pyramids that share corners with two equivalent ORbMg5 octahedra, corners with three equivalent OMg5 square pyramids, and edges with eight OMg6 octahedra. The corner-sharing octahedral tilt angles are 2°. In the third O2- site, O2- is bonded to six Mg2+ atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra, edges with seven ORbMg5 octahedra, and edges with two equivalent OMg5 square pyramids. The corner-sharing octahedra tilt angles range from 1–14°. In the fourth O2- site, O2- is bonded to two equivalent Rb1+ and four Mg2+ atoms to form ORb2Mg4 octahedra that share corners with four ORb2Mg4 octahedra and edges with eight ORbMg5 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fifth O2- site, O2- is bonded in a distorted square co-planar geometry to four Mg2+ atoms. In the sixth O2- site, O2- is bonded to six Mg2+ atoms to form OMg6 octahedra that share corners with six ORb2Mg4 octahedra and edges with twelve ORbMg5 octahedra. The corner-sharing octahedral tilt angles are 0°. In the seventh O2- site, O2- is bonded to six Mg2+ atoms to form OMg6 octahedra that share corners with four OMg6 octahedra, edges with eight OMg6 octahedra, and edges with four equivalent OMg5 square pyramids. The corner-sharing octahedral tilt angles are 0°. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to one Rb1+, four Mg2+, and one C3+ atom. In the ninth O2- site, O2- is bonded to six Mg2+ atoms to form OMg6 octahedra that share corners with four equivalent OMg6 octahedra, edges with ten ORbMg5 octahedra, and edges with two equivalent OMg5 square pyramids. The corner-sharing octahedra tilt angles range from 0–1°.