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DOE OSTI · 1268644

Materials Data on MgAs2S2(OF3)4 by Materials Project

Abstract

MgAs2S2(OF3)4 crystallizes in the monoclinic P2_1/c space group. The structure is one-dimensional and consists of two MgAs2S2(OF3)4 ribbons oriented in the (0, 1, 0) direction. Mg2+ is bonded to two O2- and four F1- atoms to form MgO2F4 octahedra that share corners with four AsF6 octahedra. The corner-sharing octahedra tilt angles range from 5–30°. Both Mg–O bond lengths are 2.12 Å. There are a spread of Mg–F bond distances ranging from 1.99–2.02 Å. There are two inequivalent As5+ sites. In the first As5+ site, As5+ is bonded to six F1- atoms to form AsF6 octahedra that share corners with two equivalent MgO2F4 octahedra. The corner-sharing octahedral tilt angles are 30°. There are a spread of As–F bond distances ranging from 1.74–1.85 Å. In the second As5+ site, As5+ is bonded to six F1- atoms to form AsF6 octahedra that share corners with two equivalent MgO2F4 octahedra. The corner-sharing octahedra tilt angles range from 5–10°. There are a spread of As–F bond distances ranging from 1.74–1.85 Å. There are two inequivalent S4+ sites. In the first S4+ site, S4+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.44 Å) and one longer (1.46 Å) S–O bond length. In the second S4+ site, S4+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.44 Å) and one longer (1.46 Å) S–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Mg2+ and one S4+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one S4+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Mg2+ and one S4+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one S4+ atom. There are twelve inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the fourth F1- site, F1- is bonded in a bent 150 degrees geometry to one Mg2+ and 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 bent 150 degrees geometry to one Mg2+ and one As5+ atom. In the eighth F1- site, F1- is bonded in a linear geometry to one Mg2+ and one As5+ atom. In the ninth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the tenth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the eleventh F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the twelfth F1- site, F1- is bonded in a linear geometry to one Mg2+ and one As5+ atom.

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2020-04-29. Materials Data on MgAs2S2(OF3)4 by Materials Project. https://doi.org/10.17188/1268644

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