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DOE OSTI · 1204274

Materials Data on Cu7PSe6 by Materials Project

Abstract

Cu7PSe6 crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. there are seven inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded in a distorted T-shaped geometry to three Se2- atoms. There are a spread of Cu–Se bond distances ranging from 2.40–2.45 Å. In the second Cu1+ site, Cu1+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are a spread of Cu–Se bond distances ranging from 2.46–2.64 Å. In the third Cu1+ site, Cu1+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are a spread of Cu–Se bond distances ranging from 2.42–2.84 Å. In the fourth Cu1+ site, Cu1+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share corners with two equivalent PSe4 tetrahedra. There are a spread of Cu–Se bond distances ranging from 2.41–2.59 Å. In the fifth Cu1+ site, Cu1+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are a spread of Cu–Se bond distances ranging from 2.46–2.61 Å. In the sixth Cu1+ site, Cu1+ is bonded in a bent 150 degrees geometry to two Se2- atoms. There are one shorter (2.34 Å) and one longer (2.41 Å) Cu–Se bond lengths. In the seventh Cu1+ site, Cu1+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are a spread of Cu–Se bond distances ranging from 2.41–2.91 Å. P5+ is bonded to four Se2- atoms to form PSe4 tetrahedra that share corners with two equivalent CuSe4 tetrahedra. There are a spread of P–Se bond distances ranging from 2.23–2.25 Å. There are six inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to three Cu1+ and one P5+ atom to form corner-sharing SeCu3P tetrahedra. In the second Se2- site, Se2- is bonded to three Cu1+ and one P5+ atom to form distorted corner-sharing SeCu3P tetrahedra. In the third Se2- site, Se2- is bonded to three Cu1+ and one P5+ atom to form corner-sharing SeCu3P trigonal pyramids. In the fourth Se2- site, Se2- is bonded to three Cu1+ and one P5+ atom to form distorted corner-sharing SeCu3P tetrahedra. In the fifth Se2- site, Se2- is bonded in a 6-coordinate geometry to six Cu1+ atoms. In the sixth Se2- site, Se2- is bonded in a 7-coordinate geometry to seven Cu1+ atoms.

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2020-07-15. Materials Data on Cu7PSe6 by Materials Project. https://doi.org/10.17188/1204274

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36 MATERIALS SCIENCE↗