Materials Data on La4MgSi4(C2O11)2 by Materials Project

MgLa4Si4(C2O11)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 2.07–2.22 Å. There are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of La–O bond distances ranging from 2.42–3.09 Å. In the second La3+ site, La3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of La–O bond distances ranging from 2.40–2.67 Å. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent MgO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–49°. There are a spread of Si–O bond distances ranging from 1.60–1.70 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one MgO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 29°. There are a spread of Si–O bond distances ranging from 1.59–1.82 Å. There are two inequivalent C+3.50+ sites. In the first C+3.50+ site, C+3.50+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of C–O bond distances ranging from 1.38–1.42 Å. In the second C+3.50+ site, C+3.50+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of C–O bond distances ranging from 1.23–1.35 Å. There are eleven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Mg2+, two La3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to two La3+ and one C+3.50+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+3.50+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one La3+ and two Si4+ atoms. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to two La3+ and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Mg2+, two La3+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to two La3+ and one C+3.50+ atom. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to two La3+ and one Si4+ atom. In the ninth O2- site, O2- is bonded in an L-shaped geometry to one La3+ and two equivalent C+3.50+ atoms. In the tenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mg2+, two equivalent La3+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two La3+, one Si4+, and one C+3.50+ atom.