DOE OSTI2020
Sr4Lu3F17 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of Sr–F bond distances ranging from 2.49–2.73 Å. In the second Sr2+ site, Sr2+ is bonded in a 10-coordinate geometry to ten F1- atoms. There are a spread of Sr–F bond distances ranging from 2.49–2.85 Å. In the third Sr2+ site, Sr2+ is bonded in a 11-coordinate geometry to eleven F1- atoms. There are a spread of Sr–F bond distances ranging from 2.48–3.05 Å. In the fourth Sr2+ site, Sr2+ is bonded in a 11-coordinate geometry to eight F1- atoms. There are a spread of Sr–F bond distances ranging from 2.48–2.78 Å. In the fifth Sr2+ site, Sr2+ is bonded in a 11-coordinate geometry to eleven F1- atoms. There are a spread of Sr–F bond distances ranging from 2.49–3.05 Å. In the sixth Sr2+ site, Sr2+ is bonded in a 11-coordinate geometry to eleven F1- atoms. There are a spread of Sr–F bond distances ranging from 2.48–3.12 Å. In the seventh Sr2+ site, Sr2+ is bonded in a 10-coordinate geometry to ten F1- atoms. There are a spread of Sr–F bond distances ranging from 2.49–2.81 Å. In the eighth Sr2+ site, Sr2+ is bonded in a 11-coordinate geometry to eleven F1- atoms. There are a spread of Sr–F bond distances ranging from 2.48–3.03 Å. There are six inequivalent Lu3+ sites. In the first Lu3+ site, Lu3+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of Lu–F bond distances ranging from 2.18–2.29 Å. In the second Lu3+ site, Lu3+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of Lu–F bond distances ranging from 2.19–2.31 Å. In the third Lu3+ site, Lu3+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of Lu–F bond distances ranging from 2.18–2.29 Å. In the fourth Lu3+ site, Lu3+ is bonded in a 9-coordinate geometry to nine F1- atoms. There are a spread of Lu–F bond distances ranging from 2.19–2.47 Å. In the fifth Lu3+ site, Lu3+ is bonded in a 9-coordinate geometry to nine F1- atoms. There are a spread of Lu–F bond distances ranging from 2.18–2.59 Å. In the sixth Lu3+ site, Lu3+ is bonded in a 9-coordinate geometry to nine F1- atoms. There are a spread of Lu–F bond distances ranging from 2.18–2.60 Å. There are thirty-four inequivalent F1- sites. In the first F1- site, F1- is bonded to six Sr2+ atoms to form a mixture of distorted corner and face-sharing FSr6 octahedra. In the second F1- site, F1- is bonded to three Sr2+ and one Lu3+ atom to form FSr3Lu tetrahedra that share corners with two equivalent FSr6 octahedra, corners with eleven FSr3Lu tetrahedra, and edges with five FSr3Lu tetrahedra. The corner-sharing octahedra tilt angles range from 52–61°. In the third F1- site, F1- is bonded to four Sr2+ atoms to form FSr4 tetrahedra that share corners with twelve FSr2Lu2 tetrahedra, edges with six FSr3Lu tetrahedra, and a faceface with one FSr6 octahedra. In the fourth F1- site, F1- is bonded to two Sr2+ and two Lu3+ atoms to form FSr2Lu2 tetrahedra that share a cornercorner with one FSr6 octahedra, corners with ten FSr3Lu tetrahedra, and edges with four FSr2Lu2 tetrahedra. The corner-sharing octahedral tilt angles are 57°. In the fifth F1- site, F1- is bonded to three Sr2+ and one Lu3+ atom to form FSr3Lu tetrahedra that share corners with two equivalent FSr6 octahedra, corners with eleven FSr3Lu tetrahedra, and edges with five FSr3Lu tetrahedra. The corner-sharing octahedra tilt angles range from 51–61°. In the sixth F1- site, F1- is bonded to three Sr2+ and one Lu3+ atom to form distorted FSr3Lu tetrahedra that share corners with eleven FSr3Lu tetrahedra, edges with five FSr3Lu tetrahedra, and a faceface with one FSr6 octahedra. In the seventh F1- site, F1- is bonded to three Sr2+ and one Lu3+ atom to form FSr3Lu tetrahedra that share corners with two equivalent FSr6 octahedra, corners with eleven FSr3Lu tetrahedra, and edges with five FSr3Lu tetrahedra. The corner-sharing octahedra tilt angles range from 52–60°. In the eighth F1- site, F1- is bonded to three Sr2+ and one Lu3+ atom to form distorted FSr3Lu tetrahedra that share corners with eleven FSr3Lu tetrahedra, edges with five FSr3Lu tetrahedra, and a faceface with one FSr6 octahedra. In the ninth F1- site, F1- is bonded to two Sr2+ and two Lu3+ atoms to form FSr2Lu2 tetrahedra that share a cornercorner with one FSr6 octahedra, corners with ten FSr3Lu tetrahedra, and edges with four FSr2Lu2 tetrahedra. The corner-sharing octahedral tilt angles are 56°. In the tenth F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Sr2+ and two Lu3+ atoms. In the eleventh F1- site, F1- is bonded in a bent 150 degrees geometry to two Lu3+ atoms. In the twelfth F1- site, F1- is bonded in a 2-coordinate geometry to two Sr2+ and two Lu3+ atoms. In the thirteenth F1- site, F1- is bonded to two Sr2+ and two Lu3+ atoms to form distorted FSr2Lu2 tetrahedra that share a cornercorner with one FSr6 octahedra, corners with ten FSr3Lu tetrahedra, and edges with four FSr3Lu tetrahedra. The corner-sharing octahedral tilt angles are 56°. In the fourteenth F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Sr2+ and two Lu3+ atoms. In the fifteenth F1- site, F1- is bonded to three Sr2+ and one Lu3+ atom to form distorted FSr3Lu tetrahedra that share corners with eleven FSr3Lu tetrahedra, edges with five FSr2Lu2 tetrahedra, and a faceface with one FSr6 octahedra. In the sixteenth F1- site, F1- is bonded in a 2-coordinate geometry to two Sr2+ and two Lu3+ atoms. In the seventeenth F1- site, F1- is bonded in a bent 150 degrees geometry to one Sr2+ and two Lu3+ atoms. In the eighteenth F1- site, F1- is bonded in a 3-coordinate geometry to three Lu3+ atoms. In the nineteenth F1- site, F1- is bonded in a distorted bent 120 degrees geometry to two Sr2+ and two Lu3+ atoms. In the twentieth F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Sr2+ and two Lu3+ atoms. In the twenty-first F1- site, F1- is bonded to three Sr2+ and one Lu3+ atom to form distorted FSr3Lu tetrahedra that share corners with eleven FSr2Lu2 tetrahedra, edges with five FSr3Lu tetrahedra, and a faceface with one FSr6 octahedra. In the twenty-second F1- site, F1- is bonded in a distorted bent 150 degrees geometry to two Sr2+ and two Lu3+ atoms. In the twenty-third F1- site, F1- is bonded to two Sr2+ and two Lu3+ atoms to form FSr2Lu2 tetrahedra that share a cornercorner with one FSr6 octahedra, corners with ten FSr3Lu tetrahedra, and edges with four FSr3Lu tetrahedra. The corner-sharing octahedral tilt angles are 57°. In the twenty-fourth F1- site, F1- is bonded in a 2-coordinate geometry to two Sr2+ and two Lu3+ atoms. In the twenty-fifth F1- site, F1- is bonded in a distorted bent 120 degrees geometry to two Sr2+ and two Lu3+ atoms. In the twenty-sixth F1- site, F1- is bonded in a 2-coordinate geometry to two Sr2+ and two Lu3+ atoms. In the twenty-seventh F1- site, F1- is bonded to two Sr2+ and two Lu3+ atoms to form distorted FSr2Lu2 tetrahedra that share a cornercorner with one FSr6 octahedra, corners with ten FSr3Lu tetrahedra, and edges with four FSr3Lu tetrahedra. The corner-sharing octahedral tilt angles are 57°. In the twenty-eighth F1- site, F1- is bonded to three Sr2+ and one Lu3+ atom to form distorted FSr3Lu tetrahedra that share corners with eleven FSr3Lu tetrahedra, edges with five FSr3Lu tetrahedra, and a faceface with one FSr6 octahedra. In the twenty-ninth F1- site, F1- is bonded to three Sr2+ and one Lu3+ atom to form FSr3Lu tetrahedra that share corners with two equivalent FSr6 octahedra, corners with eleven FSr3Lu tetrahedra, and edges with five FSr2Lu2 tetrahedra. The corner-sharing octahedra tilt angles range from 52–62°. In the thirtieth F1- site, F1- is bonded to three Sr2+ and one Lu3+ atom to form distorted FSr3Lu tetrahedra that share corners with eleven FSr3Lu tetrahedra, edges with five FSr3Lu tetrahedra, and a faceface with one FSr6 octahedra. In the thirty-first F1- site, F1- is bonded to three Sr2+ and one Lu3+ atom to form FSr3Lu tetrahedra that share corners with two equivalent FSr6 octahedra, corners with eleven FSr2Lu2 tetrahedra, and edges with five FSr3Lu tetrahedra. The corner-sharing octahedra tilt angles range from 52–59°. In the thirty-second F1- site, F1- is bonded to two Sr2+ and two Lu3+ atoms to form FSr2Lu2 tetrahedra that share a cornercorner with one FSr6 octahedra, corners with ten FSr3Lu tetrahedra, and edges with four FSr3Lu tetrahedra. The corner-sharing octahedral tilt angles are 56°. In the thirty-third F1- site, F1- is bonded to four Sr2+ atoms to form FSr4 tetrahedra that share corners with twelve FSr3Lu tetrahedra, edges with six FSr3Lu tetrahedra, and a faceface with one FSr6 octahedra. In the thirty-fourth F1- site, F1- is bonded to three Sr2+ and one Lu3+ atom to form FSr3Lu tetrahedra that share corners with two equivalent FSr6 octahedra, corners with eleven FSr4 tetrahedra, and edges with five FSr2Lu2 tetrahedra. The corner-sharing octahedra tilt angles range from 52–60°.