Materials Data on CrSiH8(O2F3)2 by Materials Project

Abstract

CrSiH8(O2F3)2 crystallizes in the monoclinic P2_1/c space group. The structure is one-dimensional and consists of two CrSiH8(O2F3)2 ribbons oriented in the (1, 0, 1) direction. Cr2+ is bonded to four O2- and two equivalent F1- atoms to form CrO4F2 octahedra that share corners with two equivalent SiF6 octahedra. The corner-sharing octahedral tilt angles are 18°. There are two shorter (2.06 Å) and two longer (2.09 Å) Cr–O bond lengths. Both Cr–F bond lengths are 2.45 Å. Si4+ is bonded to six F1- atoms to form SiF6 octahedra that share corners with two equivalent CrO4F2 octahedra. The corner-sharing octahedral tilt angles are 18°. There are a spread of Si–F bond distances ranging from 1.70–1.74 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted water-like geometry to one Cr2+ and two H1+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Cr2+ and two H1+ atoms. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted single-bond geometry to one Si4+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one Si4+ atom. In the third F1- site, F1- is bonded in a distorted single-bond geometry to one Cr2+ and one Si4+ atom.