Ca3Si2H34(C7O2)8 is Protactinium structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of two Ca3Si2H34(C7O2)8 clusters. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(6), and one O(7) atom to form distorted edge-sharing CaO6 pentagonal pyramids. The Ca(1)-O(1) bond length is 2.52 Å. The Ca(1)-O(2) bond length is 2.49 Å. The Ca(1)-O(4) bond length is 2.45 Å. The Ca(1)-O(5) bond length is 2.48 Å. The Ca(1)-O(6) bond length is 2.54 Å. The Ca(1)-O(7) bond length is 2.37 Å. In the second Ca site, Ca(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(6) atoms to form edge-sharing CaO6 octahedra. Both Ca(2)-O(2) bond lengths are 2.32 Å. Both Ca(2)-O(3) bond lengths are 2.26 Å. Both Ca(2)-O(6) bond lengths are 2.34 Å. Si(1) is bonded in a tetrahedral geometry to one C(1), one C(15), one C(22), and one C(8) atom. The Si(1)-C(1) bond length is 1.87 Å. The Si(1)-C(15) bond length is 1.87 Å. The Si(1)-C(22) bond length is 1.88 Å. The Si(1)-C(8) bond length is 1.87 Å. There are twenty-eight inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one Si(1), one C(2), and one C(6) atom. The C(1)-C(2) bond length is 1.39 Å. The C(1)-C(6) bond length is 1.40 Å. In the second C site, C(2) is bonded in a distorted single-bond geometry to one C(1), one C(3), and one H(1) atom. The C(2)-C(3) bond length is 1.39 Å. The C(2)-H(1) bond length is 0.95 Å. In the third C site, C(3) is bonded in a distorted trigonal planar geometry to one C(2), one C(4), and one H(2) atom. The C(3)-C(4) bond length is 1.39 Å. The C(3)-H(2) bond length is 0.95 Å. In the fourth C site, C(4) is bonded in a trigonal planar geometry to one C(3), one C(5), and one C(7) atom. The C(4)-C(5) bond length is 1.39 Å. The C(4)-C(7) bond length is 1.50 Å. In the fifth C site, C(5) is bonded in a distorted single-bond geometry to one C(4) and one H(3) atom. The C(5)-H(3) bond length is 0.95 Å. In the sixth C site, C(6) is bonded in a distorted single-bond geometry to one C(1) and one H(4,9,12) atom. The C(6)-H(4,9,12) bond length is 0.95 Å. In the seventh C site, C(7) is bonded in a distorted bent 120 degrees geometry to one C(4), one O(1), and one O(2) atom. The C(7)-O(1) bond length is 1.25 Å. The C(7)-O(2) bond length is 1.27 Å. In the eighth C site, C(8) is bonded in a trigonal planar geometry to one Si(1), one C(13), and one C(9) atom. The C(8)-C(13) bond length is 1.39 Å. The C(8)-C(9) bond length is 1.40 Å. In the ninth C site, C(9) is bonded in a distorted single-bond geometry to one C(8) and one H(5,8) atom. The C(9)-H(5,8) bond length is 0.95 Å. In the tenth C site, C(10) is bonded in a distorted single-bond geometry to one C(11) and one H(6,7) atom. The C(10)-C(11) bond length is 1.39 Å. The C(10)-H(6,7) bond length is 0.95 Å. In the eleventh C site, C(11) is bonded in a trigonal planar geometry to one C(10), one C(12), and one C(14) atom. The C(11)-C(12) bond length is 1.40 Å. The C(11)-C(14) bond length is 1.49 Å. In the twelfth C site, C(12) is bonded in a distorted single-bond geometry to one C(11) and one H(6,7) atom. The C(12)-H(6,7) bond length is 0.95 Å. In the thirteenth C site, C(13) is bonded in a distorted single-bond geometry to one C(8) and one H(5,8) atom. The C(13)-H(5,8) bond length is 0.95 Å. In the fourteenth C site, C(14) is bonded in a distorted bent 120 degrees geometry to one C(11), one O(3), and one O(4) atom. The C(14)-O(3) bond length is 1.25 Å. The C(14)-O(4) bond length is 1.27 Å. In the fifteenth C site, C(15) is bonded in a trigonal planar geometry to one Si(1), one C(16), and one C(20) atom. The C(15)-C(16) bond length is 1.39 Å. The C(15)-C(20) bond length is 1.39 Å. In the sixteenth C site, C(16) is bonded in a distorted single-bond geometry to one C(15) and one H(4,9,12) atom. The C(16)-H(4,9,12) bond length is 0.95 Å. In the seventeenth C site, C(17) is bonded in a distorted single-bond geometry to one C(18) and one H(10) atom. The C(17)-C(18) bond length is 1.38 Å. The C(17)-H(10) bond length is 0.95 Å. In the eighteenth C site, C(18) is bonded in a trigonal planar geometry to one C(17), one C(19), and one C(21) atom. The C(18)-C(19) bond length is 1.39 Å. The C(18)-C(21) bond length is 1.50 Å. In the nineteenth C site, C(19) is bonded in a distorted single-bond geometry to one C(18) and one H(11) atom. The C(19)-H(11) bond length is 0.95 Å. In the twentieth C site, C(20) is bonded in a distorted single-bond geometry to one C(15) and one H(4,9,12) atom. The C(20)-H(4,9,12) bond length is 0.95 Å. In the twenty-first C site, C(21) is bonded in a distorted bent 120 degrees geometry to one C(18), one O(5), and one O(6) atom. The C(21)-O(5) bond length is 1.25 Å. The C(21)-O(6) bond length is 1.27 Å. In the twenty-second C site, C(22) is bonded in a distorted trigonal planar geometry to one Si(1), one C(23), and one C(27) atom. The C(22)-C(23) bond length is 1.39 Å. The C(22)-C(27) bond length is 1.41 Å. In the twenty-third C site, C(23) is bonded in a distorted single-bond geometry to one C(22) and one H(13) atom. The C(23)-H(13) bond length is 0.95 Å. In the twenty-fourth C site, C(24) is bonded in a distorted single-bond geometry to one C(25) and one H(14,15) atom. The C(24)-C(25) bond length is 1.39 Å. The C(24)-H(14,15) bond length is 0.95 Å. In the twenty-fifth C site, C(25) is bonded in a trigonal planar geometry to one C(24), one C(26), and one C(28) atom. The C(25)-C(26) bond length is 1.39 Å. The C(25)-C(28) bond length is 1.49 Å. In the twenty-sixth C site, C(26) is bonded in a distorted single-bond geometry to one C(25) and one H(14,15) atom. The C(26)-H(14,15) bond length is 0.95 Å. In the twenty-seventh C site, C(27) is bonded in a distorted single-bond geometry to one C(22) and one H(16) atom. The C(27)-H(16) bond length is 0.95 Å. In the twenty-eighth C site, C(28) is bonded in a distorted bent 120 degrees geometry to one C(25), one O(7), and one O(8) atom. The C(28)-O(7) bond length is 1.22 Å. The C(28)-O(8) bond length is 1.31 Å. There are twelve inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one C(2) atom. In the second H site, H(2) is bonded in a single-bond geometry to one C(3) atom. In the third H site, H(3) is bonded in a single-bond geometry to one C(5) atom. In the fourth H site, H(4,9,12) is bonded in a single-bond geometry to one C(6) atom. In the fifth H site, H(5,8) is bonded in a single-bond geometry to one C(9) atom. In the sixth H site, H(6,7) is bonded in a single-bond geometry to one C(10) atom. In the seventh H site, H(10) is bonded in a single-bond geometry to one C(17) atom. In the eighth H site, H(11) is bonded in a single-bond geometry to one C(19) atom. In the ninth H site, H(13) is bonded in a single-bond geometry to one C(23) atom. In the tenth H site, H(14,15) is bonded in a single-bond geometry to one C(24) atom. In the eleventh H site, H(16) is bonded in a single-bond geometry to one C(27) atom. In the twelfth H site, H(17) is bonded in a distorted single-bond geometry to one O(4) and one O(8) atom. The H(17)-O(4) bond length is 1.72 Å. The H(17)-O(8) bond length is 0.90 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted L-shaped geometry to one Ca(1) and one C(7) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Ca(1), one Ca(2), and one C(7) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Ca(2) and one C(14) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ca(1), one C(14), and one H(17) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one Ca(1) and one C(21) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Ca(1), one Ca(2), and one C(21) atom. In the seventh O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Ca(1) and one C(28) atom. In the eighth O site, O(8) is bonded in a water-like geometry to one C(28) and one H(17) atom. Linkers: 4 [O]C(=O)c1ccc([Si](c2ccc(C([O])=O)cc2)(c2ccc(C([O])=O)cc2)c2ccc(C(=O)O)cc2)cc1. Metal clusters: 2 O[C]O[Ca]O[C]O[Ca]O[C]O[Ca]O[C]O.[O][C]=O.[O][C]=O.[O][C]=O.[O][C]=O. The MOF has largest included sphere 6.57 A, density 0.88 g/cm3, surface area 4641.42 m2/g, accessible volume 0.54 cm3/g