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DOE OSTI · 1759697

Materials Data on VAsNO4F by Materials Project

Abstract

VAsNO4F crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. there are two inequivalent V5+ sites. In the first V5+ site, V5+ is bonded to four O2- and two F1- atoms to form VO4F2 octahedra that share corners with two equivalent VO4F2 octahedra and corners with four AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 42–44°. There are a spread of V–O bond distances ranging from 1.88–1.99 Å. There is one shorter (1.97 Å) and one longer (1.98 Å) V–F bond length. In the second V5+ site, V5+ is bonded to four O2- and two F1- atoms to form VO4F2 octahedra that share corners with two equivalent VO4F2 octahedra and corners with four AsO4 tetrahedra. The corner-sharing octahedra tilt angles range from 42–44°. There are a spread of V–O bond distances ranging from 1.81–1.99 Å. Both V–F bond lengths are 2.01 Å. There are two inequivalent As5+ sites. In the first As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with four VO4F2 octahedra. The corner-sharing octahedra tilt angles range from 40–49°. There are a spread of As–O bond distances ranging from 1.70–1.74 Å. In the second As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with four VO4F2 octahedra. The corner-sharing octahedra tilt angles range from 43–49°. There is three shorter (1.71 Å) and one longer (1.75 Å) As–O bond length. There are two inequivalent N1- sites. In the first N1- site, N1- is bonded in a 5-coordinate geometry to four O2- and one F1- atom. There are a spread of N–O bond distances ranging from 2.75–3.07 Å. The N–F bond length is 2.84 Å. In the second N1- site, N1- is bonded in a 6-coordinate geometry to five O2- and one F1- atom. There are a spread of N–O bond distances ranging from 2.70–3.13 Å. The N–F bond length is 2.97 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one V5+, one As5+, and two N1- atoms. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V5+, one As5+, and one N1- atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one V5+, one As5+, and one N1- atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one V5+, one As5+, and one N1- atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V5+ and one As5+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V5+, one As5+, and two N1- atoms. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one V5+, one As5+, and one N1- atom. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one V5+, one As5+, and one N1- atom. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted bent 150 degrees geometry to two V5+ and one N1- atom. In the second F1- site, F1- is bonded in a distorted bent 150 degrees geometry to two V5+ and one N1- atom.

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2020-09-03. Materials Data on VAsNO4F by Materials Project. https://doi.org/10.17188/1759697

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