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DOE OSTI · 1270384

Materials Data on Ca(CO2)2 by Materials Project

Abstract

CaC2O4 crystallizes in the monoclinic P2/m space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to seven O2- atoms to form distorted edge-sharing CaO7 pentagonal bipyramids. There are a spread of Ca–O bond distances ranging from 2.36–2.50 Å. In the second Ca2+ site, Ca2+ is bonded to seven O2- atoms to form distorted edge-sharing CaO7 pentagonal bipyramids. There are a spread of Ca–O bond distances ranging from 2.35–2.49 Å. There are four inequivalent C3+ sites. In the first C3+ site, C3+ is bonded in a bent 120 degrees geometry to two equivalent O2- atoms. Both C–O bond lengths are 1.27 Å. In the second C3+ site, C3+ is bonded in a bent 120 degrees geometry to two equivalent O2- atoms. Both C–O bond lengths are 1.27 Å. In the third C3+ site, C3+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.26 Å) and one longer (1.28 Å) C–O bond length. In the fourth C3+ site, C3+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.26 Å) and one longer (1.28 Å) C–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ca2+ and one C3+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ca2+ and one C3+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ca2+ and one C3+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one Ca2+ and one C3+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to one Ca2+ and one C3+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ca2+ and one C3+ atom.

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2020-07-23. Materials Data on Ca(CO2)2 by Materials Project. https://doi.org/10.17188/1270384

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36 MATERIALS SCIENCE↗