(CaH4(CO3)2)8O2 crystallizes in the tetragonal I4 space group. The structure consists of two water atoms inside a CaH4(CO3)2 framework. In the CaH4(CO3)2 framework, Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), two equivalent O(5), and two equivalent O(6) atoms. There are two inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one O(3) and one O(5) atom. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to one O(4) and one O(6) atom. There are four inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(1) atom. In the third H site, H(3) is bonded in a single-bond geometry to one O(2) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(2) atom. There are six inequivalent O sites. In the first O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Ca(1) and one C(1) atom. In the second O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Ca(1) and one C(2) atom. In the third O site, O(5) is bonded in a distorted single-bond geometry to two equivalent Ca(1) and one C(1) atom. In the fourth O site, O(6) is bonded in a distorted single-bond geometry to two equivalent Ca(1) and one C(2) atom. In the fifth O site, O(1) is bonded in a distorted water-like geometry to one Ca(1), one H(1), and one H(2) atom. In the sixth O site, O(2) is bonded in a distorted water-like geometry to one Ca(1), one H(3), and one H(4) atom.
(CaH4(CO3)2)8O2 crystallizes in the tetragonal I4 space group. The structure consists of two water atoms inside a CaH4(CO3)2 framework. In the CaH4(CO3)2 framework, Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), two equivalent O(5), and two equivalent O(6) atoms. The Ca(1)-O(1) bond length is 2.41 Å. The Ca(1)-O(2) bond length is 2.41 Å. The Ca(1)-O(3) bond length is 2.49 Å. The Ca(1)-O(4) bond length is 2.49 Å. There is one shorter (2.48 Å) and one longer (2.53 Å) Ca(1)-O(5) bond length. There is one shorter (2.48 Å) and one longer (2.53 Å) Ca(1)-O(6) bond length. There are two inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one O(3) and one O(5) atom. The C(1)-O(3) bond length is 1.27 Å. The C(1)-O(5) bond length is 1.27 Å. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to one O(4) and one O(6) atom. The C(2)-O(4) bond length is 1.27 Å. The C(2)-O(6) bond length is 1.27 Å. There are four inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) atom. The H(1)-O(1) bond length is 0.98 Å. In the second H site, H(2) is bonded in a single-bond geometry to one O(1) atom. The H(2)-O(1) bond length is 0.98 Å. In the third H site, H(3) is bonded in a single-bond geometry to one O(2) atom. The H(3)-O(2) bond length is 0.98 Å. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(2) atom. The H(4)-O(2) bond length is 0.99 Å. There are six inequivalent O sites. In the first O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Ca(1) and one C(1) atom. In the second O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Ca(1) and one C(2) atom. In the third O site, O(5) is bonded in a distorted single-bond geometry to two equivalent Ca(1) and one C(1) atom. In the fourth O site, O(6) is bonded in a distorted single-bond geometry to two equivalent Ca(1) and one C(2) atom. In the fifth O site, O(1) is bonded in a distorted water-like geometry to one Ca(1), one H(1), and one H(2) atom. In the sixth O site, O(2) is bonded in a distorted water-like geometry to one Ca(1), one H(3), and one H(4) atom.