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DOE OSTI · 1193303

Materials Data on Na2Cu3(GeO3)4 by Materials Project

Abstract

Na2Cu3(GeO3)4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Na1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Na–O bond distances ranging from 2.35–3.02 Å. There are two inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Cu–O bond distances ranging from 1.92–1.99 Å. In the second Cu2+ site, Cu2+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.95 Å) and two longer (1.97 Å) Cu–O bond length. There are two inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded to four O2- atoms to form corner-sharing GeO4 tetrahedra. There are a spread of Ge–O bond distances ranging from 1.74–1.81 Å. In the second Ge4+ site, Ge4+ is bonded to four O2- atoms to form corner-sharing GeO4 tetrahedra. There are a spread of Ge–O bond distances ranging from 1.75–1.80 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Na1+, one Cu2+, and one Ge4+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Na1+, one Cu2+, and one Ge4+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two Cu2+ and one Ge4+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Na1+ and two Ge4+ atoms. In the fifth O2- site, O2- is bonded to two equivalent Na1+ and two Ge4+ atoms to form distorted ONa2Ge2 trigonal pyramids that share corners with three equivalent ONaCu2Ge trigonal pyramids and an edgeedge with one ONa2Ge2 trigonal pyramid. In the sixth O2- site, O2- is bonded to one Na1+, two Cu2+, and one Ge4+ atom to form distorted corner-sharing ONaCu2Ge trigonal pyramids.

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2020-07-14. Materials Data on Na2Cu3(GeO3)4 by Materials Project. https://doi.org/10.17188/1193303

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