DOI: 10.17188/1306187
title: Materials Data on Cs2HfO3 by Materials Project

description: Cs2HfO3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are six inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Cs–O bond distances ranging from 2.92–3.41 Å. In the second Cs1+ site, Cs1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Cs–O bond distances ranging from 3.06–3.76 Å. In the third Cs1+ site, Cs1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Cs–O bond distances ranging from 2.87–3.40 Å. In the fourth Cs1+ site, Cs1+ is bonded to six O2- atoms to form distorted CsO6 pentagonal pyramids that share corners with three HfO4 tetrahedra, an edgeedge with one CsO6 pentagonal pyramid, edges with two equivalent HfO4 tetrahedra, and an edgeedge with one CsO5 trigonal bipyramid. There are a spread of Cs–O bond distances ranging from 3.06–3.50 Å. In the fifth Cs1+ site, Cs1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Cs–O bond distances ranging from 2.98–3.67 Å. In the sixth Cs1+ site, Cs1+ is bonded to five O2- atoms to form distorted CsO5 trigonal bipyramids that share corners with four HfO4 tetrahedra, an edgeedge with one CsO6 pentagonal pyramid, and an edgeedge with one HfO4 tetrahedra. There are a spread of Cs–O bond distances ranging from 3.11–3.24 Å. There are three inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded to four O2- atoms to form HfO4 tetrahedra that share corners with two HfO4 tetrahedra, a cornercorner with one CsO5 trigonal bipyramid, and edges with two equivalent CsO6 pentagonal pyramids. There are a spread of Hf–O bond distances ranging from 1.92–2.02 Å. In the second Hf4+ site, Hf4+ is bonded to four O2- atoms to form HfO4 tetrahedra that share a cornercorner with one CsO6 pentagonal pyramid, corners with two HfO4 tetrahedra, and corners with two equivalent CsO5 trigonal bipyramids. There are a spread of Hf–O bond distances ranging from 1.92–2.01 Å. In the third Hf4+ site, Hf4+ is bonded to four O2- atoms to form HfO4 tetrahedra that share corners with two equivalent CsO6 pentagonal pyramids, corners with two HfO4 tetrahedra, a cornercorner with one CsO5 trigonal bipyramid, and an edgeedge with one CsO5 trigonal bipyramid. There are a spread of Hf–O bond distances ranging from 1.92–2.01 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to five Cs1+ and one Hf4+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Cs1+ and two Hf4+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two Cs1+ and two Hf4+ atoms. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to five Cs1+ and one Hf4+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to four Cs1+ and one Hf4+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to five Cs1+ and one Hf4+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to four Cs1+ and one Hf4+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two Cs1+ and two Hf4+ atoms. In the ninth O2- site, O2- is bonded in a 1-coordinate geometry to four Cs1+ and one Hf4+ atom.