DOI: 10.17188/1731230
title: Materials Data on Ba2NaCe2Ti2FeSi8HO27 by Materials Project

description: (NaBa2Ce2Ti2FeSi8O27)2H2 crystallizes in the monoclinic C2 space group. The structure is three-dimensional and consists of two hydrogen molecules and one NaBa2Ce2Ti2FeSi8O27 framework. In the NaBa2Ce2Ti2FeSi8O27 framework, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with six SiO4 tetrahedra and an edgeedge with one FeO5 trigonal bipyramid. There are a spread of Na–O bond distances ranging from 2.30–2.82 Å. Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.77–3.18 Å. Ce3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ce–O bond distances ranging from 2.31–2.76 Å. Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with four SiO4 tetrahedra and an edgeedge with one TiO6 octahedra. There are a spread of Ti–O bond distances ranging from 1.92–2.14 Å. Fe2+ is bonded to five O2- atoms to form FeO5 trigonal bipyramids that share corners with four SiO4 tetrahedra and an edgeedge with one NaO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.98–2.25 Å. There are four inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one NaO6 octahedra, a cornercorner with one TiO6 octahedra, and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 34–73°. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one NaO6 octahedra, a cornercorner with one TiO6 octahedra, and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 44–46°. There is two shorter (1.63 Å) and two longer (1.67 Å) Si–O bond length. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one NaO6 octahedra, a cornercorner with one TiO6 octahedra, corners with two SiO4 tetrahedra, and a cornercorner with one FeO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 49–70°. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one TiO6 octahedra, corners with two SiO4 tetrahedra, and a cornercorner with one FeO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 51°. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. There are fifteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, one Ti4+, and one Si4+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ce3+, one Ti4+, and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted L-shaped geometry to two equivalent Ba2+ and two equivalent Ti4+ atoms. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ba2+ and two Si4+ atoms. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to one Ce3+, one Fe2+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a trigonal planar geometry to two equivalent Ce3+ and one Fe2+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ba2+ and two Si4+ atoms. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ba2+ and two Si4+ atoms. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, one Ti4+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ba2+ and two Si4+ atoms. In the eleventh O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Na1+, one Ce3+, and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a distorted L-shaped geometry to two equivalent Ba2+ and two equivalent Ti4+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted single-bond geometry to one Na1+, two equivalent Ce3+, and one Si4+ atom. In the fourteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ce3+, one Ti4+, and one Si4+ atom. In the fifteenth O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, one Ce3+, one Fe2+, and one Si4+ atom.