Materials Data on Nd7V(Se2O)4 by Materials Project

Abstract

Nd7VO4Se8 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. there are four inequivalent Nd3+ sites. In the first Nd3+ site, Nd3+ is bonded in a 3-coordinate geometry to three Se2- and three O2- atoms. There are one shorter (3.03 Å) and two longer (3.25 Å) Nd–Se bond lengths. There are two shorter (2.37 Å) and one longer (2.38 Å) Nd–O bond lengths. In the second Nd3+ site, Nd3+ is bonded in a 3-coordinate geometry to five Se2- and three O2- atoms. There are a spread of Nd–Se bond distances ranging from 3.08–3.19 Å. There are two shorter (2.38 Å) and one longer (2.40 Å) Nd–O bond lengths. In the third Nd3+ site, Nd3+ is bonded to six Se2- atoms to form edge-sharing NdSe6 octahedra. There are two shorter (2.92 Å) and four longer (2.96 Å) Nd–Se bond lengths. In the fourth Nd3+ site, Nd3+ is bonded in a 1-coordinate geometry to six Se2- and one O2- atom. There are a spread of Nd–Se bond distances ranging from 2.94–3.23 Å. The Nd–O bond length is 2.44 Å. V3+ is bonded in a distorted linear geometry to four equivalent Se2- and two equivalent O2- atoms. All V–Se bond lengths are 2.70 Å. Both V–O bond lengths are 1.98 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 4-coordinate geometry to two Nd3+ and two equivalent V3+ atoms. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to five Nd3+ atoms. In the third Se2- site, Se2- is bonded to five Nd3+ atoms to form distorted SeNd5 square pyramids that share corners with two equivalent SeNd5 square pyramids, corners with five ONd3V tetrahedra, edges with three equivalent SeNd5 square pyramids, and an edgeedge with one ONd4 tetrahedra. In the fourth Se2- site, Se2- is bonded in a 5-coordinate geometry to five Nd3+ atoms. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to three Nd3+ and one V3+ atom to form ONd3V tetrahedra that share corners with two equivalent SeNd5 square pyramids, corners with three equivalent ONd3V tetrahedra, and edges with two equivalent ONd4 tetrahedra. In the second O2- site, O2- is bonded to four Nd3+ atoms to form ONd4 tetrahedra that share corners with three equivalent SeNd5 square pyramids, corners with two equivalent ONd4 tetrahedra, an edgeedge with one SeNd5 square pyramid, and edges with two equivalent ONd3V tetrahedra.