Hf(O4Cl)4 is Indium-like structured and crystallizes in the monoclinic Cc space group. The structure is zero-dimensional and consists of four Hf(O4Cl)4 clusters. Hf(1) is bonded to one O(1), one O(13), one O(16), one O(4), one O(5), one O(6), one O(8), and one O(9) atom to form distorted HfO8 hexagonal bipyramids that share  an edgeedge with one Cl(2)O4 tetrahedra;  an edgeedge with one Cl(3)O4 tetrahedra; and edges with two equivalent Cl(1,4)O4 tetrahedra. There are fifteen inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to one Hf(1) and one Cl(3) atom. In the second O site, O(2,14) is bonded in a single-bond geometry to one Cl(2) atom. In the third O site, O(3) is bonded in a single-bond geometry to one Cl(2) atom. In the fourth O site, O(4) is bonded in a water-like geometry to one Hf(1) and one Cl(1,4) atom. In the fifth O site, O(5) is bonded in a water-like geometry to one Hf(1) and one Cl(2) atom. In the sixth O site, O(6) is bonded in a water-like geometry to one Hf(1) and one Cl(1,4) atom. In the seventh O site, O(7) is bonded in a single-bond geometry to one Cl(1,4) atom. In the eighth O site, O(8) is bonded in a water-like geometry to one Hf(1) and one Cl(1,4) atom. In the ninth O site, O(9) is bonded in a water-like geometry to one Hf(1) and one Cl(3) atom. In the tenth O site, O(10) is bonded in a single-bond geometry to one Cl(1,4) atom. In the eleventh O site, O(11) is bonded in a single-bond geometry to one Cl(1,4) atom. In the twelfth O site, O(12) is bonded in a single-bond geometry to one Cl(3) atom. In the thirteenth O site, O(13) is bonded in a water-like geometry to one Hf(1) and one Cl(2) atom. In the fourteenth O site, O(15) is bonded in a single-bond geometry to one Cl(1,4) atom. In the fifteenth O site, O(16) is bonded in a water-like geometry to one Hf(1) and one Cl(1,4) atom. There are three inequivalent Cl sites. In the first Cl site, Cl(1,4) is bonded to one O(10), one O(11), one O(16), and one O(6) atom to form ClO4 tetrahedra that share  an edgeedge with one Hf(1)O8 hexagonal bipyramid. In the second Cl site, Cl(2) is bonded to one O(13); one O(2,14); one O(3); and one O(5) atom to form ClO4 tetrahedra that share  an edgeedge with one Hf(1)O8 hexagonal bipyramid. In the third Cl site, Cl(3) is bonded to one O(1); one O(12); one O(2,14); and one O(9) atom to form ClO4 tetrahedra that share  an edgeedge with one Hf(1)O8 hexagonal bipyramid.
Hf(O4Cl)4 is Indium-like structured and crystallizes in the monoclinic Cc space group. The structure is zero-dimensional and consists of four Hf(O4Cl)4 clusters. Hf(1) is bonded to one O(1), one O(13), one O(16), one O(4), one O(5), one O(6), one O(8), and one O(9) atom to form distorted HfO8 hexagonal bipyramids that share  an edgeedge with one Cl(2)O4 tetrahedra;  an edgeedge with one Cl(3)O4 tetrahedra; and edges with two equivalent Cl(1,4)O4 tetrahedra. The Hf(1)-O(1) bond length is 2.17 Å. The Hf(1)-O(13) bond length is 2.17 Å. The Hf(1)-O(16) bond length is 2.18 Å. The Hf(1)-O(4) bond length is 2.17 Å. The Hf(1)-O(5) bond length is 2.17 Å. The Hf(1)-O(6) bond length is 2.17 Å. The Hf(1)-O(8) bond length is 2.18 Å. The Hf(1)-O(9) bond length is 2.18 Å. There are fifteen inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to one Hf(1) and one Cl(3) atom. The O(1)-Cl(3) bond length is 1.52 Å. In the second O site, O(2,14) is bonded in a single-bond geometry to one Cl(2) atom. The O(2,14)-Cl(2) bond length is 1.40 Å. In the third O site, O(3) is bonded in a single-bond geometry to one Cl(2) atom. The O(3)-Cl(2) bond length is 1.40 Å. In the fourth O site, O(4) is bonded in a water-like geometry to one Hf(1) and one Cl(1,4) atom. The O(4)-Cl(1,4) bond length is 1.52 Å. In the fifth O site, O(5) is bonded in a water-like geometry to one Hf(1) and one Cl(2) atom. The O(5)-Cl(2) bond length is 1.51 Å. In the sixth O site, O(6) is bonded in a water-like geometry to one Hf(1) and one Cl(1,4) atom. The O(6)-Cl(1,4) bond length is 1.52 Å. In the seventh O site, O(7) is bonded in a single-bond geometry to one Cl(1,4) atom. The O(7)-Cl(1,4) bond length is 1.40 Å. In the eighth O site, O(8) is bonded in a water-like geometry to one Hf(1) and one Cl(1,4) atom. The O(8)-Cl(1,4) bond length is 1.51 Å. In the ninth O site, O(9) is bonded in a water-like geometry to one Hf(1) and one Cl(3) atom. The O(9)-Cl(3) bond length is 1.51 Å. In the tenth O site, O(10) is bonded in a single-bond geometry to one Cl(1,4) atom. The O(10)-Cl(1,4) bond length is 1.40 Å. In the eleventh O site, O(11) is bonded in a single-bond geometry to one Cl(1,4) atom. The O(11)-Cl(1,4) bond length is 1.40 Å. In the twelfth O site, O(12) is bonded in a single-bond geometry to one Cl(3) atom. The O(12)-Cl(3) bond length is 1.40 Å. In the thirteenth O site, O(13) is bonded in a water-like geometry to one Hf(1) and one Cl(2) atom. The O(13)-Cl(2) bond length is 1.52 Å. In the fourteenth O site, O(15) is bonded in a single-bond geometry to one Cl(1,4) atom. The O(15)-Cl(1,4) bond length is 1.40 Å. In the fifteenth O site, O(16) is bonded in a water-like geometry to one Hf(1) and one Cl(1,4) atom. The O(16)-Cl(1,4) bond length is 1.51 Å. There are three inequivalent Cl sites. In the first Cl site, Cl(1,4) is bonded to one O(10), one O(11), one O(16), and one O(6) atom to form ClO4 tetrahedra that share  an edgeedge with one Hf(1)O8 hexagonal bipyramid. In the second Cl site, Cl(2) is bonded to one O(13); one O(2,14); one O(3); and one O(5) atom to form ClO4 tetrahedra that share  an edgeedge with one Hf(1)O8 hexagonal bipyramid. In the third Cl site, Cl(3) is bonded to one O(1); one O(12); one O(2,14); and one O(9) atom to form ClO4 tetrahedra that share  an edgeedge with one Hf(1)O8 hexagonal bipyramid. The Cl(3)-O(2,14) bond length is 1.40 Å.