ErC12H4(O4F3)2 is Indium-like structured and crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of one ErC12H4(O4F3)2 cluster. Er(1) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(4), one O(5), one O(6), one O(7), one O(8), and two equivalent O(3) atoms. The Er(1)-O(1) bond length is 2.37 Å. The Er(1)-O(2) bond length is 2.37 Å. The Er(1)-O(4) bond length is 2.36 Å. The Er(1)-O(5) bond length is 2.36 Å. The Er(1)-O(6) bond length is 2.40 Å. The Er(1)-O(7) bond length is 2.41 Å. The Er(1)-O(8) bond length is 2.41 Å. There is one shorter (2.30 Å) and one longer (2.75 Å) Er(1)-O(3) bond length. There are nine inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one C(2), one O(3), and one O(6) atom. The C(1)-C(2) bond length is 1.51 Å. The C(1)-O(3) bond length is 1.27 Å. The C(1)-O(6) bond length is 1.26 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one C(1) and two equivalent C(3,4) atoms. Both C(2)-C(3,4) bond lengths are 1.39 Å. In the third C site, C(3,4) is bonded in a distorted single-bond geometry to one C(2) and one F(1,2) atom. The C(3,4)-F(1,2) bond length is 1.35 Å. In the fourth C site, C(5,6) is bonded in a single-bond geometry to one C(7) and one F(3,4) atom. The C(5,6)-C(7) bond length is 1.41 Å. The C(5,6)-F(3,4) bond length is 1.35 Å. In the fifth C site, C(7) is bonded in a trigonal planar geometry to one C(8) and two equivalent C(5,6) atoms. The C(7)-C(8) bond length is 1.49 Å. In the sixth C site, C(8) is bonded in a distorted bent 120 degrees geometry to one C(7), one O(1), and one O(2) atom. The C(8)-O(1) bond length is 1.28 Å. The C(8)-O(2) bond length is 1.28 Å. In the seventh C site, C(9,10) is bonded in a distorted single-bond geometry to one C(11) and one F(5,6) atom. The C(9,10)-C(11) bond length is 1.39 Å. The C(9,10)-F(5,6) bond length is 1.35 Å. In the eighth C site, C(11) is bonded in a trigonal planar geometry to one C(12) and two equivalent C(9,10) atoms. The C(11)-C(12) bond length is 1.51 Å. In the ninth C site, C(12) is bonded in a distorted bent 120 degrees geometry to one C(11), one O(4), and one O(5) atom. The C(12)-O(4) bond length is 1.27 Å. The C(12)-O(5) bond length is 1.27 Å. There are two inequivalent H sites. In the first H site, H(1,2) is bonded in a single-bond geometry to one O(7) atom. The H(1,2)-O(7) bond length is 0.98 Å. In the second H site, H(3,4) is bonded in a single-bond geometry to one O(7) atom. The H(3,4)-O(7) bond length is 0.99 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted L-shaped geometry to one Er(1) and one C(8) atom. In the second O site, O(2) is bonded in a distorted L-shaped geometry to one Er(1) and one C(8) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to two equivalent Er(1) and one C(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Er(1) and one C(12) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Er(1) and one C(12) atom. In the sixth O site, O(6) is bonded in a distorted water-like geometry to one Er(1) and one C(1) atom. In the seventh O site, O(7) is bonded in a distorted water-like geometry to one Er(1); one H(1,2); and one H(3,4) atom. In the eighth O site, O(8) is bonded in a distorted water-like geometry to one Er(1); one H(1,2); and one H(3,4) atom. The O(8)-H(1,2) bond length is 0.98 Å. The O(8)-H(3,4) bond length is 0.99 Å. There are three inequivalent F sites. In the first F site, F(1,2) is bonded in a single-bond geometry to one C(3,4) atom. In the second F site, F(3,4) is bonded in a single-bond geometry to one C(5,6) atom. In the third F site, F(5,6) is bonded in a single-bond geometry to one C(9,10) atom. Linkers: 3 [O]C(=O)c1c(F)c(F)c(C([O])=O)c(F)c1F. Metal clusters: 1 O.O.O.O.[C]1O[Er]234(O1)O[C]O[Er]1(O[C]O1)(O[C]O2)(O[C]O3)O[C]O4. RCSR code: sql. The MOF has largest included sphere 3.83 A, density 2.47 g/cm3, surface area 2467.07 m2/g, accessible volume 0.10 cm3/g