Hf3H8(CO2)8 crystallizes in the triclinic P1 space group. There are twelve inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(13), one O(14), one O(29), one O(31), one O(7), and one O(9) atom. The Hf(1)-O(1) bond length is 2.35 Å. The Hf(1)-O(10) bond length is 2.29 Å. The Hf(1)-O(13) bond length is 2.04 Å. The Hf(1)-O(14) bond length is 2.18 Å. The Hf(1)-O(29) bond length is 2.09 Å. The Hf(1)-O(31) bond length is 2.23 Å. The Hf(1)-O(7) bond length is 2.32 Å. The Hf(1)-O(9) bond length is 2.11 Å. In the second Hf site, Hf(2) is bonded in a 8-coordinate geometry to one O(11), one O(12), one O(13), one O(14), one O(3), one O(30), one O(32), and one O(5) atom. The Hf(2)-O(11) bond length is 2.24 Å. The Hf(2)-O(12) bond length is 2.05 Å. The Hf(2)-O(13) bond length is 2.10 Å. The Hf(2)-O(14) bond length is 2.32 Å. The Hf(2)-O(3) bond length is 2.28 Å. The Hf(2)-O(30) bond length is 2.27 Å. The Hf(2)-O(32) bond length is 2.05 Å. The Hf(2)-O(5) bond length is 2.32 Å. In the third Hf site, Hf(3) is bonded in a 8-coordinate geometry to one O(15), one O(21), one O(23), one O(24), one O(27), one O(28), one O(29), and one O(31) atom. The Hf(3)-O(15) bond length is 2.23 Å. The Hf(3)-O(21) bond length is 2.38 Å. The Hf(3)-O(23) bond length is 2.32 Å. The Hf(3)-O(24) bond length is 1.99 Å. The Hf(3)-O(27) bond length is 2.32 Å. The Hf(3)-O(28) bond length is 2.12 Å. The Hf(3)-O(29) bond length is 2.04 Å. The Hf(3)-O(31) bond length is 2.25 Å. In the fourth Hf site, Hf(4) is bonded in a 7-coordinate geometry to one O(17), one O(25), one O(26), one O(27), one O(28), one O(30), and one O(32) atom. The Hf(4)-O(17) bond length is 2.20 Å. The Hf(4)-O(25) bond length is 1.98 Å. The Hf(4)-O(26) bond length is 2.26 Å. The Hf(4)-O(27) bond length is 2.21 Å. The Hf(4)-O(28) bond length is 2.06 Å. The Hf(4)-O(30) bond length is 2.22 Å. The Hf(4)-O(32) bond length is 2.08 Å. In the fifth Hf site, Hf(5) is bonded in a 8-coordinate geometry to one O(13), one O(18), one O(2), one O(22), one O(28), one O(30), one O(31), and one O(6) atom. The Hf(5)-O(13) bond length is 2.05 Å. The Hf(5)-O(18) bond length is 2.21 Å. The Hf(5)-O(2) bond length is 2.19 Å. The Hf(5)-O(22) bond length is 2.17 Å. The Hf(5)-O(28) bond length is 2.03 Å. The Hf(5)-O(30) bond length is 2.32 Å. The Hf(5)-O(31) bond length is 2.35 Å. The Hf(5)-O(6) bond length is 2.18 Å. In the sixth Hf site, Hf(6) is bonded in a 8-coordinate geometry to one O(14), one O(16), one O(20), one O(27), one O(29), one O(32), one O(4), and one O(8) atom. The Hf(6)-O(14) bond length is 2.32 Å. The Hf(6)-O(16) bond length is 2.21 Å. The Hf(6)-O(20) bond length is 2.15 Å. The Hf(6)-O(27) bond length is 2.33 Å. The Hf(6)-O(29) bond length is 2.07 Å. The Hf(6)-O(32) bond length is 2.05 Å. The Hf(6)-O(4) bond length is 2.19 Å. The Hf(6)-O(8) bond length is 2.20 Å. In the seventh Hf site, Hf(7) is bonded in a 8-coordinate geometry to one O(33), one O(39), one O(41), one O(42), one O(45), one O(46), one O(61), and one O(63) atom. The Hf(7)-O(33) bond length is 2.35 Å. The Hf(7)-O(39) bond length is 2.32 Å. The Hf(7)-O(41) bond length is 2.11 Å. The Hf(7)-O(42) bond length is 2.29 Å. The Hf(7)-O(45) bond length is 2.04 Å. The Hf(7)-O(46) bond length is 2.18 Å. The Hf(7)-O(61) bond length is 2.08 Å. The Hf(7)-O(63) bond length is 2.23 Å. In the eighth Hf site, Hf(8) is bonded in a 8-coordinate geometry to one O(35), one O(37), one O(43), one O(44), one O(45), one O(46), one O(62), and one O(64) atom. The Hf(8)-O(35) bond length is 2.28 Å. The Hf(8)-O(37) bond length is 2.32 Å. The Hf(8)-O(43) bond length is 2.24 Å. The Hf(8)-O(44) bond length is 2.05 Å. The Hf(8)-O(45) bond length is 2.10 Å. The Hf(8)-O(46) bond length is 2.32 Å. The Hf(8)-O(62) bond length is 2.27 Å. The Hf(8)-O(64) bond length is 2.05 Å. In the ninth Hf site, Hf(9) is bonded in a 8-coordinate geometry to one O(47), one O(53), one O(55), one O(56), one O(59), one O(60), one O(61), and one O(63) atom. The Hf(9)-O(47) bond length is 2.24 Å. The Hf(9)-O(53) bond length is 2.38 Å. The Hf(9)-O(55) bond length is 2.32 Å. The Hf(9)-O(56) bond length is 1.99 Å. The Hf(9)-O(59) bond length is 2.31 Å. The Hf(9)-O(60) bond length is 2.12 Å. The Hf(9)-O(61) bond length is 2.04 Å. The Hf(9)-O(63) bond length is 2.25 Å. In the tenth Hf site, Hf(10) is bonded in a 7-coordinate geometry to one O(49), one O(57), one O(58), one O(59), one O(60), one O(62), and one O(64) atom. The Hf(10)-O(49) bond length is 2.20 Å. The Hf(10)-O(57) bond length is 1.98 Å. The Hf(10)-O(58) bond length is 2.26 Å. The Hf(10)-O(59) bond length is 2.21 Å. The Hf(10)-O(60) bond length is 2.06 Å. The Hf(10)-O(62) bond length is 2.22 Å. The Hf(10)-O(64) bond length is 2.08 Å. In the eleventh Hf site, Hf(11) is bonded in a 8-coordinate geometry to one O(34), one O(38), one O(45), one O(50), one O(54), one O(60), one O(62), and one O(63) atom. The Hf(11)-O(34) bond length is 2.19 Å. The Hf(11)-O(38) bond length is 2.18 Å. The Hf(11)-O(45) bond length is 2.05 Å. The Hf(11)-O(50) bond length is 2.21 Å. The Hf(11)-O(54) bond length is 2.17 Å. The Hf(11)-O(60) bond length is 2.03 Å. The Hf(11)-O(62) bond length is 2.32 Å. The Hf(11)-O(63) bond length is 2.35 Å. In the twelfth Hf site, Hf(12) is bonded in a 8-coordinate geometry to one O(36), one O(40), one O(46), one O(48), one O(52), one O(59), one O(61), and one O(64) atom. The Hf(12)-O(36) bond length is 2.19 Å. The Hf(12)-O(40) bond length is 2.20 Å. The Hf(12)-O(46) bond length is 2.32 Å. The Hf(12)-O(48) bond length is 2.21 Å. The Hf(12)-O(52) bond length is 2.15 Å. The Hf(12)-O(59) bond length is 2.33 Å. The Hf(12)-O(61) bond length is 2.07 Å. The Hf(12)-O(64) bond length is 2.05 Å. There are thirty-one inequivalent C sites. In the first C site, C(1,9) is bonded in a distorted bent 120 degrees geometry to one C(25), one O(1), and one O(2) atom. The C(1,9)-C(25) bond length is 1.45 Å. The C(1,9)-O(1) bond length is 1.28 Å. The C(1,9)-O(2) bond length is 1.27 Å. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to one C(22), one O(3), and one O(4) atom. The C(2)-C(22) bond length is 1.45 Å. The C(2)-O(3) bond length is 1.27 Å. The C(2)-O(4) bond length is 1.27 Å. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to one C(32), one O(5), and one O(6) atom. The C(3)-C(32) bond length is 1.45 Å. The C(3)-O(5) bond length is 1.27 Å. The C(3)-O(6) bond length is 1.28 Å. In the fourth C site, C(4) is bonded in a distorted bent 120 degrees geometry to one C(30), one O(7), and one O(8) atom. The C(4)-C(30) bond length is 1.45 Å. The C(4)-O(7) bond length is 1.28 Å. The C(4)-O(8) bond length is 1.27 Å. In the fifth C site, C(5) is bonded in a distorted bent 120 degrees geometry to one C(20), one O(15), and one O(16) atom. The C(5)-C(20) bond length is 1.44 Å. The C(5)-O(15) bond length is 1.28 Å. The C(5)-O(16) bond length is 1.27 Å. In the sixth C site, C(6) is bonded in a distorted bent 120 degrees geometry to one C(23), one O(17), and one O(18) atom. The C(6)-C(23) bond length is 1.44 Å. The C(6)-O(17) bond length is 1.28 Å. The C(6)-O(18) bond length is 1.27 Å. In the seventh C site, C(7) is bonded in a distorted bent 120 degrees geometry to one C(17), one O(19), and one O(20) atom. The C(7)-C(17) bond length is 1.45 Å. The C(7)-O(19) bond length is 1.25 Å. The C(7)-O(20) bond length is 1.29 Å. In the eighth C site, C(8) is bonded in a distorted bent 120 degrees geometry to one C(27), one O(21), and one O(22) atom. The C(8)-C(27) bond length is 1.45 Å. The C(8)-O(21) bond length is 1.27 Å. The C(8)-O(22) bond length is 1.28 Å. In the ninth C site, C(10) is bonded in a distorted bent 120 degrees geometry to one C(29), one O(35), and one O(36) atom. The C(10)-C(29) bond length is 1.45 Å. The C(10)-O(35) bond length is 1.27 Å. The C(10)-O(36) bond length is 1.27 Å. In the tenth C site, C(11) is bonded in a distorted bent 120 degrees geometry to one C(26), one O(37), and one O(38) atom. The C(11)-C(26) bond length is 1.45 Å. The C(11)-O(37) bond length is 1.27 Å. The C(11)-O(38) bond length is 1.28 Å. In the eleventh C site, C(12) is bonded in a distorted bent 120 degrees geometry to one C(21), one O(39), and one O(40) atom. The C(12)-C(21) bond length is 1.45 Å. The C(12)-O(39) bond length is 1.28 Å. The C(12)-O(40) bond length is 1.27 Å. In the twelfth C site, C(13) is bonded in a distorted bent 120 degrees geometry to one C(18), one O(47), and one O(48) atom. The C(13)-C(18) bond length is 1.44 Å. The C(13)-O(47) bond length is 1.28 Å. The C(13)-O(48) bond length is 1.27 Å. In the thirteenth C site, C(14) is bonded in a distorted bent 120 degrees geometry to one C(28), one O(49), and one O(50) atom. The C(14)-C(28) bond length is 1.44 Å. The C(14)-O(49) bond length is 1.28 Å. The C(14)-O(50) bond length is 1.27 Å. In the fourteenth C site, C(15) is bonded in a distorted bent 120 degrees geometry to one C(19), one O(51), and one O(52) atom. The C(15)-C(19) bond length is 1.45 Å. The C(15)-O(51) bond length is 1.25 Å. The C(15)-O(52) bond length is 1.29 Å. In the fifteenth C site, C(16) is bonded in a distorted bent 120 degrees geometry to one C(24), one O(53), and one O(54) atom. The C(16)-C(24) bond length is 1.45 Å. The C(16)-O(53) bond length is 1.27 Å. The C(16)-O(54) bond length is 1.28 Å. In the sixteenth C site, C(17) is bonded in a linear geometry to one C(18) and one C(7) atom. The C(17)-C(18) bond length is 1.22 Å. In the seventeenth C site, C(18) is bonded in a linear geometry to one C(13) and one C(17) atom. In the eighteenth C site, C(19) is bonded in a linear geometry to one C(15) and one C(20) atom. The C(19)-C(20) bond length is 1.22 Å. In the nineteenth C site, C(20) is bonded in a linear geometry to one C(19) and one C(5) atom. In the twentieth C site, C(21) is bonded in a linear geometry to one C(12) and one C(22) atom. The C(21)-C(22) bond length is 1.21 Å. In the twenty-first C site, C(22) is bonded in a linear geometry to one C(2) and one C(21) atom. In the twenty-second C site, C(23) is bonded in a linear geometry to one C(24) and one C(6) atom. The C(23)-C(24) bond length is 1.21 Å. In the twenty-third C site, C(24) is bonded in a linear geometry to one C(16) and one C(23) atom. In the twenty-fourth C site, C(25) is bonded in a linear geometry to one C(1,9) and one C(26) atom. The C(25)-C(26) bond length is 1.21 Å. In the twenty-fifth C site, C(26) is bonded in a linear geometry to one C(11) and one C(25) atom. In the twenty-sixth C site, C(27) is bonded in a linear geometry to one C(28) and one C(8) atom. The C(27)-C(28) bond length is 1.21 Å. In the twenty-seventh C site, C(28) is bonded in a linear geometry to one C(14) and one C(27) atom. In the twenty-eighth C site, C(29) is bonded in a linear geometry to one C(10) and one C(30) atom. The C(29)-C(30) bond length is 1.21 Å. In the twenty-ninth C site, C(30) is bonded in a linear geometry to one C(29) and one C(4) atom. In the thirtieth C site, C(31) is bonded in a linear geometry to one C(1,9) and one C(32) atom. The C(31)-C(1,9) bond length is 1.45 Å. The C(31)-C(32) bond length is 1.21 Å. In the thirty-first C site, C(32) is bonded in a linear geometry to one C(3) and one C(31) atom. There are twenty-two inequivalent H sites. In the first H site, H(1,17) is bonded in a single-bond geometry to one O(14) atom. The H(1,17)-O(14) bond length is 0.97 Å. In the second H site, H(2,18) is bonded in a single-bond geometry to one O(30) atom. The H(2,18)-O(30) bond length is 0.97 Å. In the third H site, H(3,19) is bonded in a single-bond geometry to one O(27) atom. The H(3,19)-O(27) bond length is 0.97 Å. In the fourth H site, H(4,20) is bonded in a single-bond geometry to one O(31) atom. The H(4,20)-O(31) bond length is 0.97 Å. In the fifth H site, H(5) is bonded in a single-bond geometry to one O(12) atom. The H(5)-O(12) bond length is 0.97 Å. In the sixth H site, H(6) is bonded in a single-bond geometry to one O(12) and one O(26) atom. The H(6)-O(12) bond length is 1.70 Å. The H(6)-O(26) bond length is 1.01 Å. In the seventh H site, H(7,23) is bonded in a single-bond geometry to one O(25) atom. The H(7,23)-O(25) bond length is 0.97 Å. In the eighth H site, H(8,24) is bonded in a single-bond geometry to one O(23) atom. The H(8,24)-O(23) bond length is 0.98 Å. In the ninth H site, H(9,25) is bonded in a single-bond geometry to one O(24) atom. The H(9,25)-O(24) bond length is 0.97 Å. In the tenth H site, H(10) is bonded in a single-bond geometry to one O(10) atom. The H(10)-O(10) bond length is 0.98 Å. In the eleventh H site, H(11,27) is bonded in a single-bond geometry to one O(9) atom. The H(11,27)-O(9) bond length is 0.97 Å. In the twelfth H site, H(12,28) is bonded in a linear geometry to one O(11) and one O(9) atom. The H(12,28)-O(11) bond length is 1.07 Å. The H(12,28)-O(9) bond length is 1.46 Å. In the thirteenth H site, H(13,29) is bonded in a single-bond geometry to one O(23) atom. The H(13,29)-O(23) bond length is 0.98 Å. In the fourteenth H site, H(14) is bonded in a single-bond geometry to one O(10) atom. The H(14)-O(10) bond length is 0.98 Å. In the fifteenth H site, H(15) is bonded in a single-bond geometry to one O(11) atom. The H(15)-O(11) bond length is 0.97 Å. In the sixteenth H site, H(16) is bonded in a single-bond geometry to one O(19) and one O(26) atom. The H(16)-O(19) bond length is 1.69 Å. The H(16)-O(26) bond length is 1.00 Å. In the seventeenth H site, H(21) is bonded in a single-bond geometry to one O(44) atom. The H(21)-O(44) bond length is 0.97 Å. In the eighteenth H site, H(22) is bonded in a single-bond geometry to one O(44) and one O(58) atom. The H(22)-O(44) bond length is 1.70 Å. The H(22)-O(58) bond length is 1.01 Å. In the nineteenth H site, H(26) is bonded in a single-bond geometry to one O(42) atom. The H(26)-O(42) bond length is 0.98 Å. In the twentieth H site, H(30) is bonded in a single-bond geometry to one O(42) atom. The H(30)-O(42) bond length is 0.98 Å. In the twenty-first H site, H(31) is bonded in a single-bond geometry to one O(43) atom. The H(31)-O(43) bond length is 0.97 Å. In the twenty-second H site, H(32) is bonded in a single-bond geometry to one O(58) atom. The H(32)-O(58) bond length is 1.00 Å. There are sixty-four inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Hf(1) and one C(1,9) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Hf(5) and one C(1,9) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Hf(2) and one C(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Hf(6) and one C(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Hf(2) and one C(3) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Hf(5) and one C(3) atom. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Hf(1) and one C(4) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Hf(6) and one C(4) atom. In the ninth O site, O(9) is bonded in a trigonal non-coplanar geometry to one Hf(1); one H(11,27); and one H(12,28) atom. In the tenth O site, O(10) is bonded in a distorted water-like geometry to one Hf(1), one H(10), and one H(14) atom. In the eleventh O site, O(11) is bonded in a trigonal non-coplanar geometry to one Hf(2); one H(12,28); and one H(15) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Hf(2), one H(5), and one H(6) atom. In the thirteenth O site, O(13) is bonded in a trigonal planar geometry to one Hf(1), one Hf(2), and one Hf(5) atom. In the fourteenth O site, O(14) is bonded in a single-bond geometry to one Hf(1); one Hf(2); one Hf(6); and one H(1,17) atom. In the fifteenth O site, O(15) is bonded in a distorted bent 120 degrees geometry to one Hf(3) and one C(5) atom. In the sixteenth O site, O(16) is bonded in a distorted bent 120 degrees geometry to one Hf(6) and one C(5) atom. In the seventeenth O site, O(17) is bonded in a bent 120 degrees geometry to one Hf(4) and one C(6) atom. In the eighteenth O site, O(18) is bonded in a distorted bent 120 degrees geometry to one Hf(5) and one C(6) atom. In the nineteenth O site, O(19) is bonded in a distorted single-bond geometry to one C(7) and one H(16) atom. In the twentieth O site, O(20) is bonded in a distorted bent 150 degrees geometry to one Hf(6) and one C(7) atom. In the twenty-first O site, O(21) is bonded in a distorted bent 120 degrees geometry to one Hf(3) and one C(8) atom. In the twenty-second O site, O(22) is bonded in a distorted bent 120 degrees geometry to one Hf(5) and one C(8) atom. In the twenty-third O site, O(23) is bonded in a distorted trigonal non-coplanar geometry to one Hf(3); one H(13,29); and one H(8,24) atom. In the twenty-fourth O site, O(24) is bonded in a bent 120 degrees geometry to one Hf(3) and one H(9,25) atom. In the twenty-fifth O site, O(25) is bonded in a bent 120 degrees geometry to one Hf(4) and one H(7,23) atom. In the twenty-sixth O site, O(26) is bonded in a distorted water-like geometry to one Hf(4), one H(16), and one H(6) atom. In the twenty-seventh O site, O(27) is bonded in a distorted single-bond geometry to one Hf(3); one Hf(4); one Hf(6); and one H(3,19) atom. In the twenty-eighth O site, O(28) is bonded in a trigonal planar geometry to one Hf(3), one Hf(4), and one Hf(5) atom. In the twenty-ninth O site, O(29) is bonded in a trigonal planar geometry to one Hf(1), one Hf(3), and one Hf(6) atom. In the thirtieth O site, O(30) is bonded in a single-bond geometry to one Hf(2); one Hf(4); one Hf(5); and one H(2,18) atom. In the thirty-first O site, O(31) is bonded in a single-bond geometry to one Hf(1); one Hf(3); one Hf(5); and one H(4,20) atom. In the thirty-second O site, O(32) is bonded in a trigonal planar geometry to one Hf(2), one Hf(4), and one Hf(6) atom. In the thirty-third O site, O(33) is bonded in a distorted bent 120 degrees geometry to one Hf(7) and one C(1,9) atom. The O(33)-C(1,9) bond length is 1.28 Å. In the thirty-fourth O site, O(34) is bonded in a distorted bent 120 degrees geometry to one Hf(11) and one C(1,9) atom. The O(34)-C(1,9) bond length is 1.27 Å. In the thirty-fifth O site, O(35) is bonded in a distorted bent 120 degrees geometry to one Hf(8) and one C(10) atom. In the thirty-sixth O site, O(36) is bonded in a distorted bent 120 degrees geometry to one Hf(12) and one C(10) atom. In the thirty-seventh O site, O(37) is bonded in a distorted bent 120 degrees geometry to one Hf(8) and one C(11) atom. In the thirty-eighth O site, O(38) is bonded in a distorted bent 120 degrees geometry to one Hf(11) and one C(11) atom. In the thirty-ninth O site, O(39) is bonded in a distorted bent 120 degrees geometry to one Hf(7) and one C(12) atom. In the fortieth O site, O(40) is bonded in a distorted bent 120 degrees geometry to one Hf(12) and one C(12) atom. In the forty-first O site, O(41) is bonded in a trigonal non-coplanar geometry to one Hf(7); one H(11,27); and one H(12,28) atom. The O(41)-H(11,27) bond length is 0.97 Å. The O(41)-H(12,28) bond length is 1.46 Å. In the forty-second O site, O(42) is bonded in a distorted water-like geometry to one Hf(7), one H(26), and one H(30) atom. In the forty-third O site, O(43) is bonded in a trigonal non-coplanar geometry to one Hf(8); one H(12,28); and one H(31) atom. The O(43)-H(12,28) bond length is 1.07 Å. In the forty-fourth O site, O(44) is bonded in a 3-coordinate geometry to one Hf(8), one H(21), and one H(22) atom. In the forty-fifth O site, O(45) is bonded in a trigonal planar geometry to one Hf(11), one Hf(7), and one Hf(8) atom. In the forty-sixth O site, O(46) is bonded in a single-bond geometry to one Hf(12); one Hf(7); one Hf(8); and one H(1,17) atom. The O(46)-H(1,17) bond length is 0.97 Å. In the forty-seventh O site, O(47) is bonded in a distorted bent 120 degrees geometry to one Hf(9) and one C(13) atom. In the forty-eighth O site, O(48) is bonded in a distorted bent 120 degrees geometry to one Hf(12) and one C(13) atom. In the forty-ninth O site, O(49) is bonded in a distorted bent 120 degrees geometry to one Hf(10) and one C(14) atom. In the fiftieth O site, O(50) is bonded in a distorted bent 120 degrees geometry to one Hf(11) and one C(14) atom. In the fifty-first O site, O(51) is bonded in a distorted single-bond geometry to one C(15) atom. In the fifty-second O site, O(52) is bonded in a distorted bent 150 degrees geometry to one Hf(12) and one C(15) atom. In the fifty-third O site, O(53) is bonded in a distorted bent 120 degrees geometry to one Hf(9) and one C(16) atom. In the fifty-fourth O site, O(54) is bonded in a distorted bent 120 degrees geometry to one Hf(11) and one C(16) atom. In the fifty-fifth O site, O(55) is bonded in a distorted trigonal non-coplanar geometry to one Hf(9); one H(13,29); and one H(8,24) atom. The O(55)-H(13,29) bond length is 0.98 Å. The O(55)-H(8,24) bond length is 0.98 Å. In the fifty-sixth O site, O(56) is bonded in a bent 120 degrees geometry to one Hf(9) and one H(9,25) atom. The O(56)-H(9,25) bond length is 0.97 Å. In the fifty-seventh O site, O(57) is bonded in a bent 120 degrees geometry to one Hf(10) and one H(7,23) atom. The O(57)-H(7,23) bond length is 0.97 Å. In the fifty-eighth O site, O(58) is bonded in a distorted water-like geometry to one Hf(10), one H(22), and one H(32) atom. In the fifty-ninth O site, O(59) is bonded in a distorted single-bond geometry to one Hf(10); one Hf(12); one Hf(9); and one H(3,19) atom. The O(59)-H(3,19) bond length is 0.97 Å. In the sixtieth O site, O(60) is bonded in a trigonal planar geometry to one Hf(10), one Hf(11), and one Hf(9) atom. In the sixty-first O site, O(61) is bonded in a trigonal planar geometry to one Hf(12), one Hf(7), and one Hf(9) atom. In the sixty-second O site, O(62) is bonded in a single-bond geometry to one Hf(10); one Hf(11); one Hf(8); and one H(2,18) atom. The O(62)-H(2,18) bond length is 0.97 Å. In the sixty-third O site, O(63) is bonded in a single-bond geometry to one Hf(11); one Hf(7); one Hf(9); and one H(4,20) atom. The O(63)-H(4,20) bond length is 0.97 Å. In the sixty-fourth O site, O(64) is bonded in a trigonal planar geometry to one Hf(10), one Hf(12), and one Hf(8) atom. Linkers: 8 [O]C(=O)C#CC([O])=O. Metal clusters: 1 O.O.O.O.O=[C]O[Hf]1(O[C]=O)(O[C]=O)(O[Hf](O)(O)O)O[C]O[Hf](O)(O)(O)O1.O=[C]O[Hf]12(O[C]=O)(O[C]O[Hf](O)O1)O[C]O[Hf](O)O2 ,1 O.O.O.O.O=[C]O[Hf]12(O[C]=O)(O[C]O[Hf](O)O1)O[C]O[Hf@](O)(O[C]O[Hf]1(O[C]=O)(O[C]=O)(O[Hf](O)(O)O)O[C]O[Hf](O)(O)(O)O1)O2. RCSR code: bcu. The MOF has largest included sphere 6.62 A, density 1.98 g/cm3, surface area 1811.84 m2/g, accessible volume 0.25 cm3/g