DOI: 10.17188/1667287
title: Materials Data on Nd4Mg2Ti3(Si2O11)2 by Materials Project

description: Mg2Nd4Ti3(Si2O11)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with four equivalent TiO6 octahedra and edges with two equivalent TiO6 octahedra. The corner-sharing octahedra tilt angles range from 43–60°. There are a spread of Mg–O bond distances ranging from 2.04–2.10 Å. In the second Mg2+ site, 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 1.99–2.30 Å. There are two inequivalent Nd3+ sites. In the first Nd3+ site, Nd3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Nd–O bond distances ranging from 2.38–2.89 Å. In the second Nd3+ site, Nd3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Nd–O bond distances ranging from 2.43–2.80 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 two equivalent MgO6 octahedra, corners with two equivalent TiO6 octahedra, corners with two equivalent SiO4 tetrahedra, and edges with two equivalent TiO6 octahedra. The corner-sharing octahedra tilt angles range from 36–63°. There are a spread of Ti–O bond distances ranging from 1.80–2.21 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with four equivalent TiO6 octahedra and edges with two equivalent MgO6 octahedra. The corner-sharing octahedra tilt angles range from 36–63°. There are a spread of Ti–O bond distances ranging from 1.93–2.12 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 49–52°. There are a spread of Si–O bond distances ranging from 1.61–1.67 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, corners with two equivalent TiO6 octahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 45–55°. There are a spread of Si–O bond distances ranging from 1.60–1.66 Å. There are eleven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two Nd3+, one Ti4+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to one Mg2+, two Nd3+, and one Ti4+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Mg2+, two Nd3+, and one Ti4+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two Nd3+, one Ti4+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to one Mg2+, two Nd3+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Nd3+ and three Ti4+ atoms. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to one Mg2+, one Nd3+, and two equivalent Ti4+ atoms. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to two Nd3+ and one Si4+ atom. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Nd3+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a bent 150 degrees geometry to one Nd3+ and two Si4+ atoms. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to one Mg2+, two Nd3+, and one Si4+ atom.