Materials Data on UO2 by Materials Project

Abstract

UO2 is Fluorite structured and crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent U4+ sites. In the first U4+ site, U4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of U–O bond distances ranging from 2.33–2.36 Å. In the second U4+ site, U4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of U–O bond distances ranging from 2.34–2.36 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to four U4+ atoms to form a mixture of edge and corner-sharing OU4 tetrahedra. In the second O2- site, O2- is bonded to four equivalent U4+ atoms to form a mixture of edge and corner-sharing OU4 tetrahedra. In the third O2- site, O2- is bonded to four U4+ atoms to form a mixture of edge and corner-sharing OU4 tetrahedra. In the fourth O2- site, O2- is bonded to four equivalent U4+ atoms to form a mixture of edge and corner-sharing OU4 tetrahedra.