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DOE OSTI · 1291158

Materials Data on CaAs2H6F18 by Materials Project

Abstract

CaAs2H6F18 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of two CaAs2H6F18 sheets oriented in the (0, 1, 0) direction. Ca2+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of Ca–F bond distances ranging from 2.35–2.58 Å. There are two inequivalent As5+ sites. In the first As5+ site, As5+ is bonded in an octahedral geometry to six F1- atoms. There are a spread of As–F bond distances ranging from 1.74–1.84 Å. In the second As5+ site, As5+ is bonded in an octahedral geometry to six F1- atoms. There are a spread of As–F bond distances ranging from 1.74–1.82 Å. There are six inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one F1- atom. The H–F bond length is 0.95 Å. In the second H1+ site, H1+ is bonded in a distorted single-bond geometry to two F1- atoms. There is one shorter (0.98 Å) and one longer (1.61 Å) H–F bond length. In the third H1+ site, H1+ is bonded in a single-bond geometry to two F1- atoms. There is one shorter (0.96 Å) and one longer (1.64 Å) H–F bond length. In the fourth H1+ site, H1+ is bonded in a linear geometry to two F1- atoms. There is one shorter (1.00 Å) and one longer (1.44 Å) H–F bond length. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one F1- atom. The H–F bond length is 0.97 Å. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one F1- atom. The H–F bond length is 0.96 Å. There are eighteen inequivalent F1- sites. In the first F1- site, F1- is bonded in a 1-coordinate geometry to one As5+ and one H1+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one Ca2+ and one H1+ atom. In the third F1- site, F1- is bonded in a distorted single-bond geometry to one Ca2+ and one H1+ atom. In the fourth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the fifth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the sixth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the seventh F1- site, F1- is bonded in a distorted bent 120 degrees geometry to one As5+ and one H1+ atom. In the eighth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the ninth F1- site, F1- is bonded in a distorted single-bond geometry to one Ca2+ and one H1+ atom. In the tenth F1- site, F1- is bonded in a distorted single-bond geometry to one Ca2+ and one H1+ atom. In the eleventh F1- site, F1- is bonded in a bent 120 degrees geometry to one As5+ and one H1+ atom. In the twelfth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the thirteenth F1- site, F1- is bonded in a distorted single-bond geometry to one Ca2+ and one H1+ atom. In the fourteenth F1- site, F1- is bonded in a distorted single-bond geometry to one As5+ atom. In the fifteenth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the sixteenth F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Ca2+ and one As5+ atom. In the seventeenth F1- site, F1- is bonded in a bent 150 degrees geometry to one Ca2+ and one As5+ atom. In the eighteenth F1- site, F1- is bonded in a single-bond geometry to one Ca2+ and one H1+ atom.

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2020-05-29. Materials Data on CaAs2H6F18 by Materials Project. https://doi.org/10.17188/1291158

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36 MATERIALS SCIENCE↗