Sr3U6O28 crystallizes in the triclinic P1 space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 7-coordinate geometry to one O(1), one O(19), one O(24), one O(25), one O(27), one O(4), and one O(6) atom. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one O(18), one O(2), one O(20), one O(23), one O(26), one O(28), one O(3), and one O(5) atom. In the third Sr site, Sr(3) is bonded in a 8-coordinate geometry to one O(1), one O(18), one O(19), one O(24), one O(26), one O(28), one O(3), and one O(5) atom. There are six inequivalent U sites. In the first U site, U(1) is bonded in a 6-coordinate geometry to one O(1), one O(13), one O(15), one O(23), one O(7), and one O(9) atom. In the second U site, U(2) is bonded in a 6-coordinate geometry to one O(10), one O(14), one O(16), one O(2), one O(24), and one O(8) atom. In the third U site, U(3) is bonded in a 7-coordinate geometry to one O(10), one O(12), one O(13), one O(16), one O(25), one O(3), and one O(7) atom. In the fourth U site, U(4) is bonded in a 7-coordinate geometry to one O(11), one O(14), one O(15), one O(26), one O(4), one O(8), and one O(9) atom. In the fifth U site, U(5) is bonded in a 6-coordinate geometry to one O(11), one O(13), one O(16), one O(27), one O(5), and one O(7) atom. In the sixth U site, U(6) is bonded in a 6-coordinate geometry to one O(12), one O(14), one O(15), one O(28), one O(6), and one O(8) atom. There are twenty-eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Sr(1), one Sr(3), and one U(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Sr(2) and one U(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Sr(2), one Sr(3), and one U(3) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Sr(1) and one U(4) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one Sr(2), one Sr(3), and one U(5) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Sr(1) and one U(6) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one U(1), one U(3), and one U(5) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one U(2), one U(4), and one U(6) atom. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one U(1) and one U(4) atom. In the tenth O site, O(10) is bonded in a distorted bent 150 degrees geometry to one U(2) and one U(3) atom. In the eleventh O site, O(11) is bonded in a distorted bent 150 degrees geometry to one U(4) and one U(5) atom. In the twelfth O site, O(12) is bonded in a distorted bent 150 degrees geometry to one U(3) and one U(6) atom. In the thirteenth O site, O(13) is bonded in a distorted bent 150 degrees geometry to one U(1), one U(3), and one U(5) atom. In the fourteenth O site, O(14) is bonded in a distorted bent 150 degrees geometry to one U(2), one U(4), and one U(6) atom. In the fifteenth O site, O(15) is bonded in a trigonal planar geometry to one U(1), one U(4), and one U(6) atom. In the sixteenth O site, O(16) is bonded in a trigonal planar geometry to one U(2), one U(3), and one U(5) atom. In the seventeenth O site, O(17) is bonded in a bent 120 degrees geometry to one O(19) and one O(21) atom. In the eighteenth O site, O(18) is bonded in a distorted trigonal planar geometry to one Sr(2), one Sr(3), and one O(22) atom. In the nineteenth O site, O(19) is bonded in a distorted trigonal planar geometry to one Sr(1), one Sr(3), and one O(17) atom. In the twentieth O site, O(20) is bonded in a distorted bent 150 degrees geometry to one Sr(2) and one O(22) atom. In the twenty-first O site, O(21) is bonded in a single-bond geometry to one O(17) atom. In the twenty-second O site, O(22) is bonded in a bent 120 degrees geometry to one O(18) and one O(20) atom. In the twenty-third O site, O(23) is bonded in a distorted bent 120 degrees geometry to one Sr(2) and one U(1) atom. In the twenty-fourth O site, O(24) is bonded in a distorted single-bond geometry to one Sr(1), one Sr(3), and one U(2) atom. In the twenty-fifth O site, O(25) is bonded in a distorted single-bond geometry to one Sr(1) and one U(3) atom. In the twenty-sixth O site, O(26) is bonded in a distorted trigonal planar geometry to one Sr(2), one Sr(3), and one U(4) atom. In the twenty-seventh O site, O(27) is bonded in a 2-coordinate geometry to one Sr(1) and one U(5) atom. In the twenty-eighth O site, O(28) is bonded in a distorted single-bond geometry to one Sr(2), one Sr(3), and one U(6) atom.
Sr3U6O28 crystallizes in the triclinic P1 space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 7-coordinate geometry to one O(1), one O(19), one O(24), one O(25), one O(27), one O(4), and one O(6) atom. The Sr(1)-O(1) bond length is 2.72 Å. The Sr(1)-O(19) bond length is 2.70 Å. The Sr(1)-O(24) bond length is 2.72 Å. The Sr(1)-O(25) bond length is 2.61 Å. The Sr(1)-O(27) bond length is 2.58 Å. The Sr(1)-O(4) bond length is 2.62 Å. The Sr(1)-O(6) bond length is 2.58 Å. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one O(18), one O(2), one O(20), one O(23), one O(26), one O(28), one O(3), and one O(5) atom. The Sr(2)-O(18) bond length is 2.72 Å. The Sr(2)-O(2) bond length is 2.57 Å. The Sr(2)-O(20) bond length is 2.98 Å. The Sr(2)-O(23) bond length is 2.56 Å. The Sr(2)-O(26) bond length is 2.64 Å. The Sr(2)-O(28) bond length is 2.73 Å. The Sr(2)-O(3) bond length is 2.64 Å. The Sr(2)-O(5) bond length is 2.72 Å. In the third Sr site, Sr(3) is bonded in a 8-coordinate geometry to one O(1), one O(18), one O(19), one O(24), one O(26), one O(28), one O(3), and one O(5) atom. The Sr(3)-O(1) bond length is 2.67 Å. The Sr(3)-O(18) bond length is 2.69 Å. The Sr(3)-O(19) bond length is 2.66 Å. The Sr(3)-O(24) bond length is 2.69 Å. The Sr(3)-O(26) bond length is 2.66 Å. The Sr(3)-O(28) bond length is 2.65 Å. The Sr(3)-O(3) bond length is 2.67 Å. The Sr(3)-O(5) bond length is 2.65 Å. There are six inequivalent U sites. In the first U site, U(1) is bonded in a 6-coordinate geometry to one O(1), one O(13), one O(15), one O(23), one O(7), and one O(9) atom. The U(1)-O(1) bond length is 1.93 Å. The U(1)-O(13) bond length is 2.19 Å. The U(1)-O(15) bond length is 2.23 Å. The U(1)-O(23) bond length is 1.88 Å. The U(1)-O(7) bond length is 2.23 Å. The U(1)-O(9) bond length is 2.19 Å. In the second U site, U(2) is bonded in a 6-coordinate geometry to one O(10), one O(14), one O(16), one O(2), one O(24), and one O(8) atom. The U(2)-O(10) bond length is 2.19 Å. The U(2)-O(14) bond length is 2.19 Å. The U(2)-O(16) bond length is 2.23 Å. The U(2)-O(2) bond length is 1.88 Å. The U(2)-O(24) bond length is 1.93 Å. The U(2)-O(8) bond length is 2.23 Å. In the third U site, U(3) is bonded in a 7-coordinate geometry to one O(10), one O(12), one O(13), one O(16), one O(25), one O(3), and one O(7) atom. The U(3)-O(10) bond length is 2.19 Å. The U(3)-O(12) bond length is 2.21 Å. The U(3)-O(13) bond length is 2.67 Å. The U(3)-O(16) bond length is 2.23 Å. The U(3)-O(25) bond length is 1.88 Å. The U(3)-O(3) bond length is 1.93 Å. The U(3)-O(7) bond length is 2.24 Å. In the fourth U site, U(4) is bonded in a 7-coordinate geometry to one O(11), one O(14), one O(15), one O(26), one O(4), one O(8), and one O(9) atom. The U(4)-O(11) bond length is 2.21 Å. The U(4)-O(14) bond length is 2.67 Å. The U(4)-O(15) bond length is 2.23 Å. The U(4)-O(26) bond length is 1.93 Å. The U(4)-O(4) bond length is 1.88 Å. The U(4)-O(8) bond length is 2.25 Å. The U(4)-O(9) bond length is 2.19 Å. In the fifth U site, U(5) is bonded in a 6-coordinate geometry to one O(11), one O(13), one O(16), one O(27), one O(5), and one O(7) atom. The U(5)-O(11) bond length is 2.18 Å. The U(5)-O(13) bond length is 2.20 Å. The U(5)-O(16) bond length is 2.22 Å. The U(5)-O(27) bond length is 1.88 Å. The U(5)-O(5) bond length is 1.93 Å. The U(5)-O(7) bond length is 2.23 Å. In the sixth U site, U(6) is bonded in a 6-coordinate geometry to one O(12), one O(14), one O(15), one O(28), one O(6), and one O(8) atom. The U(6)-O(12) bond length is 2.18 Å. The U(6)-O(14) bond length is 2.20 Å. The U(6)-O(15) bond length is 2.23 Å. The U(6)-O(28) bond length is 1.93 Å. The U(6)-O(6) bond length is 1.88 Å. The U(6)-O(8) bond length is 2.24 Å. There are twenty-eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Sr(1), one Sr(3), and one U(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Sr(2) and one U(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Sr(2), one Sr(3), and one U(3) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Sr(1) and one U(4) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one Sr(2), one Sr(3), and one U(5) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Sr(1) and one U(6) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one U(1), one U(3), and one U(5) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one U(2), one U(4), and one U(6) atom. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one U(1) and one U(4) atom. In the tenth O site, O(10) is bonded in a distorted bent 150 degrees geometry to one U(2) and one U(3) atom. In the eleventh O site, O(11) is bonded in a distorted bent 150 degrees geometry to one U(4) and one U(5) atom. In the twelfth O site, O(12) is bonded in a distorted bent 150 degrees geometry to one U(3) and one U(6) atom. In the thirteenth O site, O(13) is bonded in a distorted bent 150 degrees geometry to one U(1), one U(3), and one U(5) atom. In the fourteenth O site, O(14) is bonded in a distorted bent 150 degrees geometry to one U(2), one U(4), and one U(6) atom. In the fifteenth O site, O(15) is bonded in a trigonal planar geometry to one U(1), one U(4), and one U(6) atom. In the sixteenth O site, O(16) is bonded in a trigonal planar geometry to one U(2), one U(3), and one U(5) atom. In the seventeenth O site, O(17) is bonded in a bent 120 degrees geometry to one O(19) and one O(21) atom. The O(17)-O(19) bond length is 1.32 Å. The O(17)-O(21) bond length is 1.27 Å. In the eighteenth O site, O(18) is bonded in a distorted trigonal planar geometry to one Sr(2), one Sr(3), and one O(22) atom. The O(18)-O(22) bond length is 1.32 Å. In the nineteenth O site, O(19) is bonded in a distorted trigonal planar geometry to one Sr(1), one Sr(3), and one O(17) atom. In the twentieth O site, O(20) is bonded in a distorted bent 150 degrees geometry to one Sr(2) and one O(22) atom. The O(20)-O(22) bond length is 1.27 Å. In the twenty-first O site, O(21) is bonded in a single-bond geometry to one O(17) atom. In the twenty-second O site, O(22) is bonded in a bent 120 degrees geometry to one O(18) and one O(20) atom. In the twenty-third O site, O(23) is bonded in a distorted bent 120 degrees geometry to one Sr(2) and one U(1) atom. In the twenty-fourth O site, O(24) is bonded in a distorted single-bond geometry to one Sr(1), one Sr(3), and one U(2) atom. In the twenty-fifth O site, O(25) is bonded in a distorted single-bond geometry to one Sr(1) and one U(3) atom. In the twenty-sixth O site, O(26) is bonded in a distorted trigonal planar geometry to one Sr(2), one Sr(3), and one U(4) atom. In the twenty-seventh O site, O(27) is bonded in a 2-coordinate geometry to one Sr(1) and one U(5) atom. In the twenty-eighth O site, O(28) is bonded in a distorted single-bond geometry to one Sr(2), one Sr(3), and one U(6) atom.