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DOE OSTI · 1738471

Materials Data on Nd2CuSi3Rh2 by Materials Project

Abstract

Nd2Rh2CuSi3 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are two inequivalent Nd+2.50+ sites. In the first Nd+2.50+ site, Nd+2.50+ is bonded to eight Si4- atoms to form NdSi8 hexagonal bipyramids that share corners with four equivalent NdSi6 pentagonal pyramids, corners with eight RhSi4 tetrahedra, edges with four equivalent NdSi8 hexagonal bipyramids, edges with two equivalent NdSi6 pentagonal pyramids, edges with four RhSi4 tetrahedra, and faces with four equivalent NdSi8 hexagonal bipyramids. There are four shorter (3.14 Å) and four longer (3.17 Å) Nd–Si bond lengths. In the second Nd+2.50+ site, Nd+2.50+ is bonded to six Si4- atoms to form distorted NdSi6 pentagonal pyramids that share corners with four equivalent NdSi8 hexagonal bipyramids, corners with four equivalent NdSi6 pentagonal pyramids, corners with eight RhSi4 tetrahedra, edges with two equivalent NdSi8 hexagonal bipyramids, edges with two equivalent NdSi6 pentagonal pyramids, edges with four RhSi4 tetrahedra, and faces with two equivalent NdSi6 pentagonal pyramids. There are two shorter (3.12 Å) and four longer (3.17 Å) Nd–Si bond lengths. There are two inequivalent Rh3+ sites. In the first Rh3+ site, Rh3+ is bonded to four Si4- atoms to form RhSi4 tetrahedra that share corners with four equivalent NdSi8 hexagonal bipyramids, corners with four equivalent NdSi6 pentagonal pyramids, corners with four equivalent RhSi4 tetrahedra, edges with two equivalent NdSi8 hexagonal bipyramids, edges with two equivalent NdSi6 pentagonal pyramids, and edges with four equivalent RhSi4 tetrahedra. There are two shorter (2.42 Å) and two longer (2.43 Å) Rh–Si bond lengths. In the second Rh3+ site, Rh3+ is bonded to four Si4- atoms to form RhSi4 tetrahedra that share corners with four equivalent NdSi8 hexagonal bipyramids, corners with four equivalent NdSi6 pentagonal pyramids, corners with four equivalent RhSi4 tetrahedra, edges with two equivalent NdSi8 hexagonal bipyramids, edges with two equivalent NdSi6 pentagonal pyramids, and edges with four equivalent RhSi4 tetrahedra. There are two shorter (2.42 Å) and two longer (2.43 Å) Rh–Si bond lengths. Cu1+ is bonded in a trigonal planar geometry to three Si4- atoms. There are two shorter (2.36 Å) and one longer (2.42 Å) Cu–Si bond lengths. There are three inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 9-coordinate geometry to six Nd+2.50+, two equivalent Cu1+, and one Si4- atom. The Si–Si bond length is 2.44 Å. In the second Si4- site, Si4- is bonded in a 9-coordinate geometry to four equivalent Nd+2.50+, four Rh3+, and one Cu1+ atom. In the third Si4- site, Si4- is bonded in a 9-coordinate geometry to four equivalent Nd+2.50+, four Rh3+, and one Si4- atom.

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2020-05-02. Materials Data on Nd2CuSi3Rh2 by Materials Project. https://doi.org/10.17188/1738471

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