Materials Data on USe2O9 by Materials Project
USe2O9 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. U6+ is bonded to seven O2- atoms to form distorted UO7 pentagonal bipyramids that share corners with four equivalent SeO4 tetrahedra. There are a spread of U–O bond distances ranging from 1.80–2.44 Å. Se6+ is bonded to four O2- atoms to form SeO4 tetrahedra that share corners with two equivalent UO7 pentagonal bipyramids and corners with two equivalent SeO4 tetrahedra. There are a spread of Se–O bond distances ranging from 1.66–2.19 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one U6+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one U6+ atom. In the third O2- site, O2- is bonded in a linear geometry to one U6+ and one Se6+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one U6+ and one Se6+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Se6+ atoms.