(Ca4Si6O19)2(O2)3 crystallizes in the monoclinic Cm space group. The structure consists of two 7782-44-7 molecules and two water atoms inside a Ca4Si6O19 framework. In the Ca4Si6O19 framework, there are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 7-coordinate geometry to one O(10), one O(7), one O(9), two equivalent O(3), and two equivalent O(4) atoms. In the second Ca site, Ca(2) is bonded in a 7-coordinate geometry to one O(3), one O(4), one O(6), two equivalent O(10), and two equivalent O(9) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(5), one O(6), and one O(8) atom to form corner-sharing SiO4 tetrahedra. In the third Si site, Si(3) is bonded to one O(10), one O(2), one O(8), and one O(9) atom to form corner-sharing SiO4 tetrahedra. There are ten inequivalent O sites. In the first O site, O(8) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(3) atom. In the second O site, O(9) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Ca(2), and one Si(3) atom. In the third O site, O(10) is bonded to one Ca(1), two equivalent Ca(2), and one Si(3) atom to form a mixture of distorted corner and edge-sharing OCa3Si tetrahedra. In the fourth O site, O(1) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the fifth O site, O(2) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom. In the sixth O site, O(3) is bonded to one Ca(2), two equivalent Ca(1), and one Si(1) atom to form a mixture of distorted corner and edge-sharing OCa3Si tetrahedra. In the seventh O site, O(4) is bonded to one Ca(2), two equivalent Ca(1), and one Si(1) atom to form a mixture of distorted corner and edge-sharing OCa3Si tetrahedra. In the eighth O site, O(5) is bonded in a bent 150 degrees geometry to two equivalent Si(2) atoms. In the ninth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Ca(2) and one Si(2) atom. In the tenth O site, O(7) is bonded in a single-bond geometry to one Ca(1) atom.
(Ca4Si6O19)2(O2)3 crystallizes in the monoclinic Cm space group. The structure consists of two 7782-44-7 molecules and two water atoms inside a Ca4Si6O19 framework. In the Ca4Si6O19 framework, there are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 7-coordinate geometry to one O(10), one O(7), one O(9), two equivalent O(3), and two equivalent O(4) atoms. The Ca(1)-O(10) bond length is 2.43 Å. The Ca(1)-O(7) bond length is 2.51 Å. The Ca(1)-O(9) bond length is 2.41 Å. There is one shorter (2.42 Å) and one longer (2.44 Å) Ca(1)-O(3) bond length. There is one shorter (2.39 Å) and one longer (2.61 Å) Ca(1)-O(4) bond length. In the second Ca site, Ca(2) is bonded in a 7-coordinate geometry to one O(3), one O(4), one O(6), two equivalent O(10), and two equivalent O(9) atoms. The Ca(2)-O(3) bond length is 2.41 Å. The Ca(2)-O(4) bond length is 2.41 Å. The Ca(2)-O(6) bond length is 2.58 Å. There is one shorter (2.39 Å) and one longer (2.62 Å) Ca(2)-O(10) bond length. There is one shorter (2.38 Å) and one longer (2.67 Å) Ca(2)-O(9) bond length. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing SiO4 tetrahedra. The Si(1)-O(1) bond length is 1.63 Å. The Si(1)-O(2) bond length is 1.65 Å. The Si(1)-O(3) bond length is 1.64 Å. The Si(1)-O(4) bond length is 1.63 Å. In the second Si site, Si(2) is bonded to one O(1), one O(5), one O(6), and one O(8) atom to form corner-sharing SiO4 tetrahedra. The Si(2)-O(1) bond length is 1.64 Å. The Si(2)-O(5) bond length is 1.61 Å. The Si(2)-O(6) bond length is 1.64 Å. The Si(2)-O(8) bond length is 1.63 Å. In the third Si site, Si(3) is bonded to one O(10), one O(2), one O(8), and one O(9) atom to form corner-sharing SiO4 tetrahedra. The Si(3)-O(10) bond length is 1.63 Å. The Si(3)-O(2) bond length is 1.65 Å. The Si(3)-O(8) bond length is 1.63 Å. The Si(3)-O(9) bond length is 1.63 Å. There are ten inequivalent O sites. In the first O site, O(8) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(3) atom. In the second O site, O(9) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Ca(2), and one Si(3) atom. In the third O site, O(10) is bonded to one Ca(1), two equivalent Ca(2), and one Si(3) atom to form a mixture of distorted corner and edge-sharing OCa3Si tetrahedra. In the fourth O site, O(1) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the fifth O site, O(2) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom. In the sixth O site, O(3) is bonded to one Ca(2), two equivalent Ca(1), and one Si(1) atom to form a mixture of distorted corner and edge-sharing OCa3Si tetrahedra. In the seventh O site, O(4) is bonded to one Ca(2), two equivalent Ca(1), and one Si(1) atom to form a mixture of distorted corner and edge-sharing OCa3Si tetrahedra. In the eighth O site, O(5) is bonded in a bent 150 degrees geometry to two equivalent Si(2) atoms. In the ninth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Ca(2) and one Si(2) atom. In the tenth O site, O(7) is bonded in a single-bond geometry to one Ca(1) atom.