Materials Data on CsMg6BO7 by Materials Project
CsMg6BO7 crystallizes in the triclinic P1 space group. The structure is two-dimensional and consists of one CsMg6BO7 sheet oriented in the (0, 0, 1) direction. Cs is bonded in a 4-coordinate geometry to four O atoms. There are a spread of Cs–O bond distances ranging from 2.80–2.95 Å. There are six inequivalent Mg sites. In the first Mg site, Mg is bonded to five O atoms to form MgO5 square pyramids that share corners with four equivalent MgO5 square pyramids and edges with eight MgO6 octahedra. There are one shorter (1.96 Å) and four longer (2.14 Å) Mg–O bond lengths. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four equivalent MgO6 octahedra, edges with four MgO6 octahedra, and edges with four equivalent MgO5 square pyramids. The corner-sharing octahedral tilt angles are 1°. There are a spread of Mg–O bond distances ranging from 2.13–2.33 Å. In the third Mg site, Mg is bonded in a T-shaped geometry to three O atoms. There are two shorter (2.13 Å) and one longer (2.14 Å) Mg–O bond lengths. In the fourth Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share corners with four equivalent MgO6 octahedra, edges with six MgO6 octahedra, and edges with two equivalent MgO5 square pyramids. The corner-sharing octahedra tilt angles range from 2–13°. There are a spread of Mg–O bond distances ranging from 2.06–2.31 Å. In the fifth Mg site, Mg is bonded in a T-shaped geometry to three O atoms. There are two shorter (2.13 Å) and one longer (2.14 Å) Mg–O bond lengths. In the sixth Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share corners with four equivalent MgO6 octahedra, edges with six MgO6 octahedra, and edges with two equivalent MgO5 square pyramids. The corner-sharing octahedra tilt angles range from 2–14°. There are a spread of Mg–O bond distances ranging from 2.06–2.32 Å. B is bonded in a trigonal planar geometry to three O atoms. There is two shorter (1.33 Å) and one longer (1.59 Å) B–O bond length. There are seven inequivalent O sites. In the first O site, O is bonded to five Mg atoms to form OMg5 square pyramids that share corners with four equivalent OMg5 square pyramids and edges with eight OMg5B octahedra. In the second O site, O is bonded to five Mg atoms to form OMg5 square pyramids that share a cornercorner with one OMg5B octahedra, corners with four equivalent OMg5 square pyramids, and edges with four OMg6 octahedra. The corner-sharing octahedral tilt angles are 1°. In the third O site, O is bonded to five Mg and one B atom to form distorted OMg5B octahedra that share corners with four equivalent OMg5B octahedra, a cornercorner with one OMg5 square pyramid, edges with four OMg6 octahedra, and edges with four equivalent OMg5 square pyramids. The corner-sharing octahedral tilt angles are 2°. In the fourth O site, O is bonded in a 2-coordinate geometry to two equivalent Cs, one Mg, and one B atom. In the fifth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with four equivalent OMg6 octahedra, edges with six OMg5B octahedra, and edges with four OMg5 square pyramids. The corner-sharing octahedra tilt angles range from 1–6°. In the sixth O site, O is bonded in a 2-coordinate geometry to two equivalent Cs, one Mg, and one B atom. In the seventh O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with four equivalent OMg6 octahedra, edges with six OMg5B octahedra, and edges with four OMg5 square pyramids. The corner-sharing octahedra tilt angles range from 1–6°.