Materials Data on K5Eu2Si4O13F by Materials Project

Abstract

K5Eu2Si4O13F crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are five inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 12-coordinate geometry to ten O2- and two equivalent F1- atoms. There are a spread of K–O bond distances ranging from 3.00–3.45 Å. Both K–F bond lengths are 2.97 Å. In the second K1+ site, K1+ is bonded in a 1-coordinate geometry to eight O2- and one F1- atom. There are a spread of K–O bond distances ranging from 2.89–3.05 Å. The K–F bond length is 2.69 Å. In the third K1+ site, K1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of K–O bond distances ranging from 2.98–3.37 Å. In the fourth K1+ site, K1+ is bonded in a 6-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.81–2.99 Å. In the fifth K1+ site, K1+ is bonded in a 7-coordinate geometry to six O2- and one F1- atom. There are a spread of K–O bond distances ranging from 2.78–3.09 Å. The K–F bond length is 2.69 Å. There are two inequivalent Eu3+ sites. In the first Eu3+ site, Eu3+ is bonded to five O2- and one F1- atom to form EuO5F octahedra that share a cornercorner with one EuO5F octahedra and corners with five SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 2°. There are a spread of Eu–O bond distances ranging from 2.27–2.35 Å. The Eu–F bond length is 2.54 Å. In the second Eu3+ site, Eu3+ is bonded to five O2- and one F1- atom to form EuO5F octahedra that share a cornercorner with one EuO5F octahedra and corners with five SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 2°. There are a spread of Eu–O bond distances ranging from 2.29–2.35 Å. The Eu–F bond length is 2.56 Å. There are four inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three equivalent EuO5F octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 13–52°. There are a spread of Si–O bond distances ranging from 1.63–1.69 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three equivalent EuO5F octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 12–25°. There is three shorter (1.64 Å) and one longer (1.69 Å) Si–O bond length. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent EuO5F octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 25°. There is two shorter (1.62 Å) and two longer (1.67 Å) Si–O bond length. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent EuO5F octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 19°. There are a spread of Si–O bond distances ranging from 1.61–1.67 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to three K1+, one Eu3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Si4+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+, one Eu3+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to three K1+, one Eu3+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to three K1+, one Eu3+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 5-coordinate geometry to three equivalent K1+, one Eu3+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to three K1+ and two Si4+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to four K1+, one Eu3+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to three K1+ and two Si4+ atoms. F1- is bonded to four K1+ and two Eu3+ atoms to form corner-sharing FK4Eu2 octahedra. The corner-sharing octahedral tilt angles are 7°.