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DOE OSTI · 1263369

Materials Data on Ca20Er10F69 by Materials Project

Abstract

Ca20Er10F69 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are eleven inequivalent Ca sites. In the first Ca site, Ca is bonded in a 10-coordinate geometry to ten F atoms. There are a spread of Ca–F bond distances ranging from 2.38–2.89 Å. In the second Ca site, Ca is bonded in a 10-coordinate geometry to ten F atoms. There are a spread of Ca–F bond distances ranging from 2.38–2.81 Å. In the third Ca site, Ca is bonded in a 10-coordinate geometry to ten F atoms. There are a spread of Ca–F bond distances ranging from 2.37–2.93 Å. In the fourth Ca site, Ca is bonded in a 10-coordinate geometry to seven F atoms. There are a spread of Ca–F bond distances ranging from 2.32–2.60 Å. In the fifth Ca site, Ca is bonded in a 10-coordinate geometry to ten F atoms. There are a spread of Ca–F bond distances ranging from 2.32–2.95 Å. In the sixth Ca site, Ca is bonded in a 10-coordinate geometry to ten F atoms. There are a spread of Ca–F bond distances ranging from 2.38–2.84 Å. In the seventh Ca site, Ca is bonded in a 10-coordinate geometry to ten F atoms. There are a spread of Ca–F bond distances ranging from 2.32–2.91 Å. In the eighth Ca site, Ca is bonded in a 7-coordinate geometry to seven F atoms. There are a spread of Ca–F bond distances ranging from 2.32–2.58 Å. In the ninth Ca site, Ca is bonded in a 8-coordinate geometry to eight F atoms. There are a spread of Ca–F bond distances ranging from 2.28–2.43 Å. In the tenth Ca site, Ca is bonded in a body-centered cubic geometry to eight F atoms. All Ca–F bond lengths are 2.37 Å. In the eleventh Ca site, Ca is bonded in a body-centered cubic geometry to eight F atoms. All Ca–F bond lengths are 2.36 Å. There are five inequivalent Er sites. In the first Er site, Er is bonded in a 8-coordinate geometry to nine F atoms. There are a spread of Er–F bond distances ranging from 2.22–3.00 Å. In the second Er site, Er is bonded in a 9-coordinate geometry to nine F atoms. There are a spread of Er–F bond distances ranging from 2.18–2.89 Å. In the third Er site, Er is bonded in a 9-coordinate geometry to nine F atoms. There are a spread of Er–F bond distances ranging from 2.18–2.89 Å. In the fourth Er site, Er is bonded in a 8-coordinate geometry to eight F atoms. There are a spread of Er–F bond distances ranging from 2.20–2.32 Å. In the fifth Er site, Er is bonded in a 8-coordinate geometry to eight F atoms. There are a spread of Er–F bond distances ranging from 2.20–2.32 Å. There are thirty-five inequivalent F sites. In the first F site, F is bonded in a 4-coordinate geometry to three Ca and one Er atom. In the second F site, F is bonded to three Ca and one Er atom to form FCa3Er tetrahedra that share a cornercorner with one FEr6 octahedra, corners with eleven FCa3Er tetrahedra, and edges with five FCa3Er tetrahedra. The corner-sharing octahedral tilt angles are 56°. In the third F site, F is bonded to three Ca and one Er atom to form a mixture of corner and edge-sharing FCa3Er tetrahedra. In the fourth F site, F is bonded to three Ca and one Er atom to form FCa3Er tetrahedra that share a cornercorner with one FEr6 octahedra, corners with eleven FCa3Er tetrahedra, and edges with five FCa3Er tetrahedra. The corner-sharing octahedral tilt angles are 56°. In the fifth F site, F is bonded in a 2-coordinate geometry to two Ca and two Er atoms. In the sixth F site, F is bonded to three Ca and one Er atom to form a mixture of corner and edge-sharing FCa3Er tetrahedra. In the seventh F site, F is bonded to two Ca and two equivalent Er atoms to form FCa2Er2 tetrahedra that share corners with two equivalent FEr6 octahedra, corners with ten FCa3Er tetrahedra, and edges with four FCa2Er2 tetrahedra. The corner-sharing octahedral tilt angles are 57°. In the eighth F site, F is bonded to four Ca atoms to form a mixture of corner and edge-sharing FCa4 tetrahedra. In the ninth F site, F is bonded to two Ca and two equivalent Er atoms to form a mixture of corner and edge-sharing FCa2Er2 tetrahedra. In the tenth F site, F is bonded in a distorted bent 150 degrees geometry to two Er atoms. In the eleventh F site, F is bonded to three Ca and one Er atom to form FCa3Er tetrahedra that share a cornercorner with one FEr6 octahedra, corners with eleven FCa3Er tetrahedra, and edges with five FCa4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. In the twelfth F site, F is bonded in a distorted bent 150 degrees geometry to one Ca and two Er atoms. In the thirteenth F site, F is bonded to three Ca and one Er atom to form a mixture of corner and edge-sharing FCa3Er tetrahedra. In the fourteenth F site, F is bonded in a distorted bent 150 degrees geometry to one Ca and two Er atoms. In the fifteenth F site, F is bonded to three Ca and one Er atom to form FCa3Er tetrahedra that share a cornercorner with one FEr6 octahedra, corners with eleven FCa3Er tetrahedra, and edges with five FCa3Er tetrahedra. The corner-sharing octahedral tilt angles are 56°. In the sixteenth F site, F is bonded in a 2-coordinate geometry to one Ca and two Er atoms. In the seventeenth F site, F is bonded to four Ca atoms to form FCa4 tetrahedra that share corners with eleven FCa3Er tetrahedra and edges with five FCa4 tetrahedra. In the eighteenth F site, F is bonded to three Ca and one Er atom to form a mixture of corner and edge-sharing FCa3Er tetrahedra. In the nineteenth F site, F is bonded to three Ca and one Er atom to form FCa3Er tetrahedra that share a cornercorner with one FEr6 octahedra, corners with twelve FCa3Er tetrahedra, and edges with five FCa2Er2 tetrahedra. The corner-sharing octahedral tilt angles are 52°. In the twentieth F site, F is bonded in a 2-coordinate geometry to one Ca and two Er atoms. In the twenty-first F site, F is bonded to three Ca and one Er atom to form FCa3Er tetrahedra that share a cornercorner with one FEr6 octahedra, corners with twelve FCa2Er2 tetrahedra, and edges with five FCa2Er2 tetrahedra. The corner-sharing octahedral tilt angles are 53°. In the twenty-second F site, F is bonded in a 4-coordinate geometry to three Ca and one Er atom. In the twenty-third F site, F is bonded to four Ca atoms to form FCa4 tetrahedra that share corners with eleven FCa3Er tetrahedra and edges with five FCa4 tetrahedra. In the twenty-fourth F site, F is bonded to four Ca atoms to form a mixture of corner and edge-sharing FCa4 tetrahedra. In the twenty-fifth F site, F is bonded in a 4-coordinate geometry to three Ca and one Er atom. In the twenty-sixth F site, F is bonded to three Ca and one Er atom to form FCa3Er tetrahedra that share a cornercorner with one FEr6 octahedra, corners with twelve FCa3Er tetrahedra, and edges with five FCa3Er tetrahedra. The corner-sharing octahedral tilt angles are 53°. In the twenty-seventh F site, F is bonded to three Ca and one Er atom to form FCa3Er tetrahedra that share a cornercorner with one FEr6 octahedra, corners with twelve FCa2Er2 tetrahedra, and edges with five FCa3Er tetrahedra. The corner-sharing octahedral tilt angles are 52°. In the twenty-eighth F site, F is bonded to two Ca and two equivalent Er atoms to form a mixture of corner and edge-sharing FCa2Er2 tetrahedra. In the twenty-ninth F site, F is bonded to four Ca atoms to form FCa4 tetrahedra that share corners with eleven FCa2Er2 tetrahedra and edges with five FCa3Er tetrahedra. In the thirtieth F site, F is bonded to four Ca atoms to form a mixture of corner and edge-sharing FCa4 tetrahedra. In the thirty-first F site, F is bonded in a 4-coordinate geometry to three Ca and one Er atom. In the thirty-second F site, F is bonded to two Ca and two equivalent Er atoms to form FCa2Er2 tetrahedra that share corners with two equivalent FEr6 octahedra, corners with ten FCa4 tetrahedra, and edges with four FCa3Er tetrahedra. The corner-sharing octahedra tilt angles range from 56–58°. In the thirty-third F site, F is bonded in a 2-coordinate geometry to two Ca and two Er atoms. In the thirty-fourth F site, F is bonded in a 2-coordinate geometry to two Ca and two Er atoms. In the thirty-fifth F site, F is bonded to six Er atoms to form corner-sharing FEr6 octahedra.

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2020-04-29. Materials Data on Ca20Er10F69 by Materials Project. https://doi.org/10.17188/1263369

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