DOI: 10.17188/1731326
title: Materials Data on U2H18C4Se3N2O17 by Materials Project

description: U2H2Se3O17((CH3)2NH2)2 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is two-dimensional and consists of eight dimethylazanium molecules and two U2H2Se3O17 sheets oriented in the (0, 0, 1) direction. In each U2H2Se3O17 sheet, there are two inequivalent U6+ sites. In the first U6+ site, U6+ is bonded to seven O2- atoms to form distorted UO7 pentagonal bipyramids that share corners with five SeO4 tetrahedra. There are a spread of U–O bond distances ranging from 1.80–2.47 Å. In the second U6+ site, U6+ is bonded to seven O2- atoms to form distorted UO7 pentagonal bipyramids that share corners with four SeO4 tetrahedra. There are a spread of U–O bond distances ranging from 1.80–2.53 Å. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to four O2- atoms to form SeO4 tetrahedra that share corners with three UO7 pentagonal bipyramids. There are a spread of Se–O bond distances ranging from 1.65–1.69 Å. In the second Se2- site, Se2- is bonded to four O2- atoms to form SeO4 tetrahedra that share corners with three UO7 pentagonal bipyramids. There are a spread of Se–O bond distances ranging from 1.64–1.70 Å. In the third Se2- site, Se2- is bonded to four O2- atoms to form SeO4 tetrahedra that share corners with three UO7 pentagonal bipyramids. There are a spread of Se–O bond distances ranging from 1.65–1.69 Å. There are seventeen inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Se2- atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one U6+ and one Se2- atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one U6+ and one Se2- atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one Se2- atom. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one U6+ and one Se2- atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one U6+ and one Se2- atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one U6+ and one Se2- atom. In the eighth O2- site, O2- is bonded in a single-bond geometry to one U6+ atom. In the ninth O2- site, O2- is bonded in a single-bond geometry to one U6+ atom. In the tenth O2- site, O2- is bonded in a water-like geometry to one U6+ and two H1+ atoms. In the eleventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one U6+ and one Se2- atom. In the twelfth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one U6+ and one Se2- atom. In the thirteenth O2- site, O2- is bonded in a 1-coordinate geometry to one U6+ and one Se2- atom. In the fourteenth O2- site, O2- is bonded in a single-bond geometry to one Se2- atom. In the fifteenth O2- site, O2- is bonded in a single-bond geometry to one U6+ atom. In the sixteenth O2- site, O2- is bonded in a single-bond geometry to one U6+ atom. In the seventeenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one U6+ and one Se2- atom.