Materials Data on BaNa3(PO4)2 by Materials Project

Abstract

Na3Ba(PO4)2 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. there are two inequivalent Na sites. In the first Na site, Na is bonded in a 1-coordinate geometry to one O atom. The Na–O bond length is 2.39 Å. In the second Na site, Na is bonded to six equivalent O atoms to form NaO6 octahedra that share corners with six equivalent PO4 tetrahedra and faces with two equivalent BaO12 cuboctahedra. All Na–O bond lengths are 2.30 Å. Ba is bonded to twelve O atoms to form distorted BaO12 cuboctahedra that share edges with six equivalent BaO12 cuboctahedra, edges with six equivalent PO4 tetrahedra, and faces with two equivalent NaO6 octahedra. There are six shorter (2.78 Å) and six longer (3.25 Å) Ba–O bond lengths. P is bonded to four O atoms to form PO4 tetrahedra that share corners with three equivalent NaO6 octahedra and edges with three equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 18°. All P–O bond lengths are 1.55 Å. There are two inequivalent O sites. In the first O site, O is bonded in a distorted linear geometry to one Na, three equivalent Ba, and one P atom. In the second O site, O is bonded in a 1-coordinate geometry to one Na, one Ba, and one P atom.