Materials Data on Ca4H16C8O25 by Materials Project
(CaH4(CO3)2)8O2 crystallizes in the tetragonal I4 space group. The structure is three-dimensional and consists of two water molecules and one CaH4(CO3)2 framework. In the CaH4(CO3)2 framework, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.41–2.53 Å. There are two inequivalent C+3.25+ sites. In the first C+3.25+ site, C+3.25+ is bonded in a bent 120 degrees geometry to two O2- atoms. Both C–O bond lengths are 1.27 Å. In the second C+3.25+ site, C+3.25+ is bonded in a bent 120 degrees geometry to two O2- atoms. Both C–O bond lengths are 1.27 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ca2+ and one C+3.25+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ca2+ and one C+3.25+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Ca2+ and one C+3.25+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Ca2+ and one C+3.25+ atom. In the fifth O2- site, O2- is bonded in a distorted water-like geometry to one Ca2+ and two H1+ atoms. In the sixth O2- site, O2- is bonded in a distorted water-like geometry to one Ca2+ and two H1+ atoms.