DOI: 10.17188/1753230
title: Materials Data on K2U(Si2O5)3 by Materials Project

description: K2U(Si2O5)3 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 8-coordinate geometry to seven O2- atoms. There are a spread of K–O bond distances ranging from 2.80–3.32 Å. In the second K1+ site, K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.72–3.28 Å. In the third K1+ site, K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.88–3.41 Å. In the fourth K1+ site, K1+ is bonded to eight O2- atoms to form distorted KO8 hexagonal bipyramids that share corners with six SiO4 tetrahedra, edges with two equivalent UO6 octahedra, and edges with three SiO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.93–3.33 Å. There are two inequivalent U4+ sites. In the first U4+ site, U4+ is bonded to six O2- atoms to form UO6 octahedra that share corners with six SiO4 tetrahedra. There are a spread of U–O bond distances ranging from 2.22–2.32 Å. In the second U4+ site, U4+ is bonded to six O2- atoms to form distorted UO6 octahedra that share corners with six SiO4 tetrahedra and edges with two equivalent KO8 hexagonal bipyramids. There are a spread of U–O bond distances ranging from 2.24–2.34 Å. There are twelve inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one UO6 octahedra, corners with three SiO4 tetrahedra, and an edgeedge with one KO8 hexagonal bipyramid. The corner-sharing octahedral tilt angles are 47°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one UO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 40°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one KO8 hexagonal bipyramid, a cornercorner with one UO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 50°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent KO8 hexagonal bipyramids, a cornercorner with one UO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 26°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the fifth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one UO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 49°. There are a spread of Si–O bond distances ranging from 1.62–1.65 Å. In the sixth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one UO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 39°. There are a spread of Si–O bond distances ranging from 1.61–1.65 Å. In the seventh Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one KO8 hexagonal bipyramid, a cornercorner with one UO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 58°. There are a spread of Si–O bond distances ranging from 1.61–1.65 Å. In the eighth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one UO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 67°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the ninth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one UO6 octahedra, corners with three SiO4 tetrahedra, and an edgeedge with one KO8 hexagonal bipyramid. The corner-sharing octahedral tilt angles are 46°. There are a spread of Si–O bond distances ranging from 1.61–1.65 Å. In the tenth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one KO8 hexagonal bipyramid, a cornercorner with one UO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Si–O bond distances ranging from 1.61–1.65 Å. In the eleventh Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one KO8 hexagonal bipyramid, a cornercorner with one UO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 41°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the twelfth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one UO6 octahedra, corners with three SiO4 tetrahedra, and an edgeedge with one KO8 hexagonal bipyramid. The corner-sharing octahedral tilt angles are 39°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. There are thirty inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one U4+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to two K1+, one U4+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two K1+, one U4+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+ and two Si4+ atoms. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Si4+ atoms. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent K1+, one U4+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the tenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+, one U4+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the twelfth O2- site, O2- is bonded in a 3-coordinate geometry to two K1+, one U4+, and one Si4+ atom. In the thirteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+ and two Si4+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+ and two Si4+ atoms. In the fifteenth O2- site, O2- is bonded in a linear geometry to two Si4+ atoms. In the sixteenth O2- site, O2- is bonded in a 2-coordinate geometry to two K1+, one U4+, and one Si4+ atom. In the seventeenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+ and two Si4+ atoms. In the eighteenth O2- site, O2- is bonded in a 1-coordinate geometry to one K1+, one U4+, and one Si4+ atom. In the nineteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+ and two Si4+ atoms. In the twentieth O2- site, O2- is bonded in a 1-coordinate geometry to two K1+, one U4+, and one Si4+ atom. In the twenty-first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+ and two Si4+ atoms. In the twenty-second O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Si4+ atoms. In the twenty-third O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Si4+ atoms. In the twenty-fourth O2- site, O2- is bonded in a 1-coordinate geometry to two K1+, one U4+, and one Si4+ atom. In the twenty-fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+ and two Si4+ atoms. In the twenty-sixth O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the twenty-seventh O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one U4+, and one Si4+ atom. In the twenty-eighth O2- site, O2- is bonded in a 1-coordinate geometry to two K1+, one U4+, and one Si4+ atom. In the twenty-ninth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+ and two Si4+ atoms. In the thirtieth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+ and two Si4+ atoms.