Sr2CaO12 crystallizes in the triclinic P1 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to one O(10), one O(2), one O(3), one O(6), one O(9), two equivalent O(1), and two equivalent O(5) atoms. In the second Sr site, Sr(2) is bonded in a 9-coordinate geometry to one O(1), one O(11), one O(12), one O(4), one O(8), two equivalent O(3), and two equivalent O(7) atoms. Ca(1) is bonded in a 10-coordinate geometry to one O(2), one O(4), one O(5), one O(6), one O(7), one O(8), two equivalent O(11), and two equivalent O(9) atoms. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Sr(2), two equivalent Sr(1), and one O(5) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Sr(1), one Ca(1), and one O(6) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Sr(1), two equivalent Sr(2), and one O(7) atom. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Sr(2), one Ca(1), and one O(8) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to two equivalent Sr(1), one Ca(1), and one O(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Sr(1), one Ca(1), and one O(2) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to two equivalent Sr(2), one Ca(1), and one O(3) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Sr(2), one Ca(1), and one O(4) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Sr(1), two equivalent Ca(1), and one O(11) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Sr(1) and one O(12) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Sr(2), two equivalent Ca(1), and one O(9) atom. In the twelfth O site, O(12) is bonded in a bent 150 degrees geometry to one Sr(2) and one O(10) atom.
Sr2CaO12 crystallizes in the triclinic P1 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to one O(10), one O(2), one O(3), one O(6), one O(9), two equivalent O(1), and two equivalent O(5) atoms. The Sr(1)-O(10) bond length is 3.00 Å. The Sr(1)-O(2) bond length is 2.54 Å. The Sr(1)-O(3) bond length is 2.57 Å. The Sr(1)-O(6) bond length is 2.55 Å. The Sr(1)-O(9) bond length is 2.59 Å. There is one shorter (2.60 Å) and one longer (2.61 Å) Sr(1)-O(1) bond length. Both Sr(1)-O(5) bond lengths are 2.52 Å. In the second Sr site, Sr(2) is bonded in a 9-coordinate geometry to one O(1), one O(11), one O(12), one O(4), one O(8), two equivalent O(3), and two equivalent O(7) atoms. The Sr(2)-O(1) bond length is 2.49 Å. The Sr(2)-O(11) bond length is 2.60 Å. The Sr(2)-O(12) bond length is 2.87 Å. The Sr(2)-O(4) bond length is 2.53 Å. The Sr(2)-O(8) bond length is 2.57 Å. Both Sr(2)-O(3) bond lengths are 2.58 Å. There is one shorter (2.53 Å) and one longer (2.54 Å) Sr(2)-O(7) bond length. Ca(1) is bonded in a 10-coordinate geometry to one O(2), one O(4), one O(5), one O(6), one O(7), one O(8), two equivalent O(11), and two equivalent O(9) atoms. The Ca(1)-O(2) bond length is 2.40 Å. The Ca(1)-O(4) bond length is 2.38 Å. The Ca(1)-O(5) bond length is 2.49 Å. The Ca(1)-O(6) bond length is 2.42 Å. The Ca(1)-O(7) bond length is 2.70 Å. The Ca(1)-O(8) bond length is 2.45 Å. There is one shorter (2.48 Å) and one longer (2.65 Å) Ca(1)-O(11) bond length. There is one shorter (2.46 Å) and one longer (2.54 Å) Ca(1)-O(9) bond length. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Sr(2), two equivalent Sr(1), and one O(5) atom. The O(1)-O(5) bond length is 1.43 Å. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Sr(1), one Ca(1), and one O(6) atom. The O(2)-O(6) bond length is 1.35 Å. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Sr(1), two equivalent Sr(2), and one O(7) atom. The O(3)-O(7) bond length is 1.39 Å. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Sr(2), one Ca(1), and one O(8) atom. The O(4)-O(8) bond length is 1.35 Å. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to two equivalent Sr(1), one Ca(1), and one O(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Sr(1), one Ca(1), and one O(2) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to two equivalent Sr(2), one Ca(1), and one O(3) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Sr(2), one Ca(1), and one O(4) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Sr(1), two equivalent Ca(1), and one O(11) atom. The O(9)-O(11) bond length is 1.36 Å. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Sr(1) and one O(12) atom. The O(10)-O(12) bond length is 1.25 Å. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Sr(2), two equivalent Ca(1), and one O(9) atom. In the twelfth O site, O(12) is bonded in a bent 150 degrees geometry to one Sr(2) and one O(10) atom.