Materials Data on U3Se5 by Materials Project
U3Se5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent U+3.33+ sites. In the first U+3.33+ site, U+3.33+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of U–Se bond distances ranging from 2.93–3.13 Å. In the second U+3.33+ site, U+3.33+ is bonded to seven Se2- atoms to form distorted edge-sharing USe7 pentagonal bipyramids. There are a spread of U–Se bond distances ranging from 2.78–2.96 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to four U+3.33+ atoms to form distorted SeU4 trigonal pyramids that share corners with six SeU5 square pyramids, corners with two equivalent SeU5 trigonal bipyramids, corners with six equivalent SeU4 trigonal pyramids, edges with three SeU5 square pyramids, edges with two equivalent SeU5 trigonal bipyramids, and an edgeedge with one SeU4 trigonal pyramid. In the second Se2- site, Se2- is bonded to five U+3.33+ atoms to form distorted SeU5 trigonal bipyramids that share corners with six SeU5 square pyramids, corners with four equivalent SeU5 trigonal bipyramids, corners with four equivalent SeU4 trigonal pyramids, edges with six SeU5 square pyramids, and edges with four equivalent SeU4 trigonal pyramids. In the third Se2- site, Se2- is bonded to five U+3.33+ atoms to form SeU5 square pyramids that share corners with four equivalent SeU5 square pyramids, corners with five equivalent SeU5 trigonal bipyramids, corners with eight equivalent SeU4 trigonal pyramids, edges with three SeU5 square pyramids, edges with two equivalent SeU5 trigonal bipyramids, edges with two equivalent SeU4 trigonal pyramids, and a faceface with one SeU5 square pyramid. In the fourth Se2- site, Se2- is bonded to five U+3.33+ atoms to form distorted SeU5 square pyramids that share corners with eight SeU5 square pyramids, a cornercorner with one SeU5 trigonal bipyramid, corners with four equivalent SeU4 trigonal pyramids, an edgeedge with one SeU5 square pyramid, edges with four equivalent SeU5 trigonal bipyramids, edges with four equivalent SeU4 trigonal pyramids, and a faceface with one SeU5 square pyramid.