Materials Data on KU3AsO15 by Materials Project

Abstract

KU3AsO15 crystallizes in the orthorhombic Cccm space group. The structure is three-dimensional. K is bonded to eight O atoms to form distorted KO8 octahedra that share corners with two equivalent KO8 octahedra and corners with four equivalent UO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 0°. There are a spread of K–O bond distances ranging from 2.72–3.35 Å. There are two inequivalent U sites. In the first U site, U is bonded to seven O atoms to form distorted UO7 pentagonal bipyramids that share corners with two equivalent KO8 octahedra, corners with two equivalent AsO4 tetrahedra, and an edgeedge with one UO7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 54°. There are a spread of U–O bond distances ranging from 1.87–2.44 Å. In the second U site, U is bonded in a distorted linear geometry to eight O atoms. There are a spread of U–O bond distances ranging from 1.80–2.53 Å. As is bonded to four equivalent O atoms to form AsO4 tetrahedra that share corners with four equivalent UO7 pentagonal bipyramids. All As–O bond lengths are 1.72 Å. There are six inequivalent O sites. In the first O site, O is bonded in a linear geometry to two equivalent K atoms. In the second O site, O is bonded in a 1-coordinate geometry to two U and one As atom. In the third O site, O is bonded in a distorted single-bond geometry to one K and one U atom. In the fourth O site, O is bonded in a single-bond geometry to one U atom. In the fifth O site, O is bonded in a trigonal planar geometry to three U atoms. In the sixth O site, O is bonded in a distorted bent 120 degrees geometry to one K and one U atom.