DOE OSTI2020
Nd4PdO7 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent Nd3+ sites. In the first Nd3+ site, Nd3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Nd–O bond distances ranging from 2.32–2.65 Å. In the second Nd3+ site, Nd3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Nd–O bond distances ranging from 2.31–2.96 Å. In the third Nd3+ site, Nd3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Nd–O bond distances ranging from 2.37–2.77 Å. In the fourth Nd3+ site, Nd3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Nd–O bond distances ranging from 2.34–2.98 Å. There are two inequivalent Pd2+ sites. In the first Pd2+ site, Pd2+ is bonded in a square co-planar geometry to four O2- atoms. There are two shorter (2.07 Å) and two longer (2.08 Å) Pd–O bond lengths. In the second Pd2+ site, Pd2+ is bonded in a square co-planar geometry to four O2- atoms. There are two shorter (2.06 Å) and two longer (2.09 Å) Pd–O bond lengths. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to three Nd3+ and two Pd2+ atoms. In the second O2- site, O2- is bonded to four Nd3+ and one Pd2+ atom to form distorted ONd4Pd square pyramids that share a cornercorner with one ONd4Pd square pyramid, corners with six ONd4 tetrahedra, an edgeedge with one ONd4Pd square pyramid, edges with two equivalent ONd4 tetrahedra, and edges with two equivalent ONd4Pd trigonal bipyramids. In the third O2- site, O2- is bonded to four Nd3+ and one Pd2+ atom to form distorted ONd4Pd trigonal bipyramids that share corners with eight ONd4 tetrahedra, a cornercorner with one ONd4Pd trigonal bipyramid, edges with two equivalent ONd4Pd square pyramids, and edges with two ONd4 tetrahedra. In the fourth O2- site, O2- is bonded to four Nd3+ atoms to form ONd4 tetrahedra that share corners with four ONd4 tetrahedra, corners with two equivalent ONd4Pd trigonal bipyramids, edges with two equivalent ONd4Pd square pyramids, edges with two ONd4 tetrahedra, and an edgeedge with one ONd4Pd trigonal bipyramid. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to five Nd3+ atoms. In the sixth O2- site, O2- is bonded to four Nd3+ atoms to form ONd4 tetrahedra that share corners with three equivalent ONd4Pd square pyramids, corners with four ONd4 tetrahedra, corners with two equivalent ONd4Pd trigonal bipyramids, edges with three ONd4 tetrahedra, and an edgeedge with one ONd4Pd trigonal bipyramid. In the seventh O2- site, O2- is bonded to four Nd3+ atoms to form ONd4 tetrahedra that share corners with three equivalent ONd4Pd square pyramids, corners with four ONd4 tetrahedra, corners with four equivalent ONd4Pd trigonal bipyramids, and edges with three ONd4 tetrahedra.