Materials Data on UBi4(AsO8)2 by Materials Project

Abstract

UBi4(AsO8)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. U6+ is bonded to six O2- atoms to form UO6 octahedra that share corners with four equivalent AsO4 tetrahedra. There are a spread of U–O bond distances ranging from 1.85–2.29 Å. There are two inequivalent Bi4+ sites. In the first Bi4+ site, Bi4+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Bi–O bond distances ranging from 2.05–2.50 Å. In the second Bi4+ site, Bi4+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Bi–O bond distances ranging from 2.22–2.98 Å. As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with two equivalent UO6 octahedra. The corner-sharing octahedra tilt angles range from 31–39°. There are a spread of As–O bond distances ranging from 1.70–1.74 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one U6+ and one Bi4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to three Bi4+ atoms. In the third O2- site, O2- is bonded to four Bi4+ atoms to form distorted edge-sharing OBi4 tetrahedra. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two Bi4+ and one As5+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to two Bi4+ and one As5+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one U6+ and one As5+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one U6+, one Bi4+, and one As5+ atom. In the eighth O2- site, O2- is bonded in a bent 120 degrees geometry to two Bi4+ atoms.