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DOE OSTI · 1282609

Materials Data on NaYF4 by Materials Project

Abstract

NaYF4 crystallizes in the monoclinic Pc space group. The structure is three-dimensional. there are three inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Na–F bond distances ranging from 2.26–2.42 Å. In the second Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Na–F bond distances ranging from 2.26–2.51 Å. In the third Na1+ site, Na1+ is bonded in a 9-coordinate geometry to nine F1- atoms. There are a spread of Na–F bond distances ranging from 2.35–2.60 Å. There are three inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded in a 9-coordinate geometry to nine F1- atoms. There are a spread of Y–F bond distances ranging from 2.32–2.41 Å. In the second Y3+ site, Y3+ is bonded in a 9-coordinate geometry to nine F1- atoms. There are a spread of Y–F bond distances ranging from 2.33–2.40 Å. In the third Y3+ site, Y3+ is bonded in a 9-coordinate geometry to nine F1- atoms. There are a spread of Y–F bond distances ranging from 2.32–2.41 Å. There are twelve inequivalent F1- sites. In the first F1- site, F1- is bonded to two Na1+ and two Y3+ atoms to form distorted FNa2Y2 tetrahedra that share corners with fifteen FNaY3 tetrahedra, corners with two equivalent FNa2Y2 trigonal pyramids, and edges with six FNa2Y2 tetrahedra. In the second F1- site, F1- is bonded to one Na1+ and three Y3+ atoms to form distorted FNaY3 tetrahedra that share corners with sixteen FNa2Y2 tetrahedra, a cornercorner with one FNa2Y2 trigonal pyramid, edges with five FNaY3 tetrahedra, and an edgeedge with one FNa2Y2 trigonal pyramid. In the third F1- site, F1- is bonded to one Na1+ and three Y3+ atoms to form distorted FNaY3 tetrahedra that share corners with fifteen FNa2Y2 tetrahedra, corners with two equivalent FNa2Y2 trigonal pyramids, and edges with six FNaY3 tetrahedra. In the fourth F1- site, F1- is bonded to two Na1+ and two Y3+ atoms to form a mixture of distorted corner and edge-sharing FNa2Y2 tetrahedra. In the fifth F1- site, F1- is bonded to two Na1+ and two Y3+ atoms to form distorted FNa2Y2 tetrahedra that share corners with fifteen FNaY3 tetrahedra, corners with two equivalent FNa2Y2 trigonal pyramids, edges with five FNa2Y2 tetrahedra, and an edgeedge with one FNa2Y2 trigonal pyramid. In the sixth F1- site, F1- is bonded to two Na1+ and two Y3+ atoms to form a mixture of distorted corner and edge-sharing FNa2Y2 tetrahedra. In the seventh F1- site, F1- is bonded to one Na1+ and three Y3+ atoms to form a mixture of distorted corner and edge-sharing FNaY3 tetrahedra. In the eighth F1- site, F1- is bonded to two Na1+ and two Y3+ atoms to form distorted FNa2Y2 tetrahedra that share corners with sixteen FNa2Y2 tetrahedra, a cornercorner with one FNa2Y2 trigonal pyramid, edges with five FNaY3 tetrahedra, and an edgeedge with one FNa2Y2 trigonal pyramid. In the ninth F1- site, F1- is bonded to two Na1+ and two Y3+ atoms to form distorted FNa2Y2 tetrahedra that share corners with fifteen FNa2Y2 tetrahedra, corners with two equivalent FNa2Y2 trigonal pyramids, edges with five FNaY3 tetrahedra, and an edgeedge with one FNa2Y2 trigonal pyramid. In the tenth F1- site, F1- is bonded to two Na1+ and two Y3+ atoms to form a mixture of distorted corner and edge-sharing FNa2Y2 tetrahedra. In the eleventh F1- site, F1- is bonded to two Na1+ and two Y3+ atoms to form distorted FNa2Y2 trigonal pyramids that share corners with seventeen FNa2Y2 tetrahedra and edges with six FNaY3 tetrahedra. In the twelfth F1- site, F1- is bonded to two Na1+ and two Y3+ atoms to form a mixture of distorted corner and edge-sharing FNa2Y2 tetrahedra.

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2020-05-01. Materials Data on NaYF4 by Materials Project. https://doi.org/10.17188/1282609

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