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DOE OSTI · 1740257

Materials Data on U2H12C2Se3(N3O8)2 by Materials Project

Abstract

U2Se3O16(CN3H6)2 crystallizes in the monoclinic P2 space group. The structure is two-dimensional and consists of four guanidinium molecules and one U2Se3O16 sheet oriented in the (0, 1, 0) direction. In the U2Se3O16 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 1.80–2.48 Å. In the second 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 1.80–2.46 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to four O2- atoms to form SeO4 tetrahedra that share corners with four UO7 pentagonal bipyramids. There is two shorter (1.67 Å) and two longer (1.68 Å) Se–O bond length. 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 is one shorter (1.64 Å) and three longer (1.69 Å) Se–O bond length. 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. In the fourth Se2- site, Se2- is bonded to four O2- atoms to form SeO4 tetrahedra that share corners with four UO7 pentagonal bipyramids. There is two shorter (1.67 Å) and two longer (1.68 Å) Se–O bond length. There are sixteen 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 single-bond geometry to one U6+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one U6+ and one Se2- atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one U6+ and one Se2- atom. In the sixth O2- site, O2- is bonded in a single-bond geometry to one U6+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one U6+ and one Se2- atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to one U6+ and one Se2- atom. In the ninth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one U6+ and one Se2- atom. In the tenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one U6+ and one Se2- atom. In the eleventh O2- site, O2- is bonded in a 2-coordinate 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 distorted bent 150 degrees 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 2-coordinate geometry to one U6+ and one Se2- atom. In the sixteenth O2- site, O2- is bonded in a single-bond geometry to one Se2- atom.

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2020-04-30. Materials Data on U2H12C2Se3(N3O8)2 by Materials Project. https://doi.org/10.17188/1740257

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