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DOE OSTI · 1192740

Materials Data on Mn2NbP12 by Materials Project

Abstract

NbMn2P12 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Nb5+ is bonded in a 8-coordinate geometry to eight P+0.75- atoms. There are a spread of Nb–P bond distances ranging from 2.56–2.69 Å. Mn2+ is bonded to six P+0.75- atoms to form MnP6 octahedra that share corners with five PNbP3 tetrahedra and an edgeedge with one MnP6 octahedra. There are a spread of Mn–P bond distances ranging from 2.20–2.32 Å. There are six inequivalent P+0.75- sites. In the first P+0.75- site, P+0.75- is bonded in a distorted single-bond geometry to one Mn2+ and three P+0.75- atoms. There are a spread of P–P bond distances ranging from 2.20–2.24 Å. In the second P+0.75- site, P+0.75- is bonded to one Nb5+ and three P+0.75- atoms to form distorted PNbP3 tetrahedra that share corners with four equivalent MnP6 octahedra and corners with four PNbP3 tetrahedra. The corner-sharing octahedra tilt angles range from 54–72°. There are a spread of P–P bond distances ranging from 2.23–2.31 Å. In the third P+0.75- site, P+0.75- is bonded in a 4-coordinate geometry to one Nb5+, one Mn2+, and two P+0.75- atoms. The P–P bond length is 2.21 Å. In the fourth P+0.75- site, P+0.75- is bonded to one Nb5+, one Mn2+, and two P+0.75- atoms to form distorted PMnNbP2 tetrahedra that share a cornercorner with one MnP6 octahedra and corners with four PNbP3 tetrahedra. The corner-sharing octahedral tilt angles are 67°. The P–P bond length is 2.30 Å. In the fifth P+0.75- site, P+0.75- is bonded in a 4-coordinate geometry to one Nb5+, one Mn2+, and two P+0.75- atoms. In the sixth P+0.75- site, P+0.75- is bonded in a 2-coordinate geometry to two equivalent Mn2+ and two P+0.75- atoms.

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2020-07-23. Materials Data on Mn2NbP12 by Materials Project. https://doi.org/10.17188/1192740

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36 MATERIALS SCIENCE↗