DOI: 10.17188/1271499
title: Materials Data on Ba6Nb14Si4O47 by Materials Project

description: Ba6Nb14Si4O47 crystallizes in the hexagonal P6_3cm space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 5-coordinate geometry to thirteen O2- atoms. There are a spread of Ba–O bond distances ranging from 2.71–3.36 Å. In the second Ba2+ site, Ba2+ is bonded in a 12-coordinate geometry to twelve O2- atoms. There are a spread of Ba–O bond distances ranging from 2.91–3.18 Å. There are five inequivalent Nb+4.71+ sites. In the first Nb+4.71+ site, Nb+4.71+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 5–68°. There are a spread of Nb–O bond distances ranging from 1.89–2.11 Å. In the second Nb+4.71+ site, Nb+4.71+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 34–43°. There are three shorter (1.93 Å) and three longer (2.12 Å) Nb–O bond lengths. In the third Nb+4.71+ site, Nb+4.71+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with four NbO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 5–32°. There are a spread of Nb–O bond distances ranging from 1.93–2.11 Å. In the fourth Nb+4.71+ site, Nb+4.71+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 15–43°. There are a spread of Nb–O bond distances ranging from 1.88–2.22 Å. In the fifth Nb+4.71+ site, Nb+4.71+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with four NbO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 15–32°. There are a spread of Nb–O bond distances ranging from 1.91–2.11 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 three equivalent NbO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 35°. There is one shorter (1.63 Å) and three longer (1.65 Å) Si–O bond length. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three equivalent NbO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 34°. There is one shorter (1.63 Å) and three longer (1.65 Å) Si–O bond length. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb+4.71+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+ and three Nb+4.71+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, one Nb+4.71+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ba2+ and two equivalent Nb+4.71+ atoms. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Ba2+ and two equivalent Nb+4.71+ atoms. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+ and two Nb+4.71+ atoms. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+ and two Nb+4.71+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, one Nb+4.71+, and one Si4+ atom. In the ninth O2- site, O2- is bonded to one Ba2+ and three Nb+4.71+ atoms to form distorted corner-sharing OBaNb3 tetrahedra. In the tenth O2- site, O2- is bonded in a linear geometry to two Si4+ atoms. In the eleventh O2- site, O2- is bonded in a linear geometry to three equivalent Ba2+ and two Nb+4.71+ atoms. In the twelfth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Ba2+ and two Nb+4.71+ atoms.