ErCPH2SO6CH2 crystallizes in the monoclinic Pc space group. The structure consists of two 02329_fluka molecules inside a ErCPH2SO6 framework. In the ErCPH2SO6 framework, Er(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form ErO6 octahedra that share corners with three equivalent P(1)CO3 tetrahedra. The Er(1)-O(1) bond length is 2.12 Å. The Er(1)-O(2) bond length is 2.16 Å. The Er(1)-O(3) bond length is 2.14 Å. The Er(1)-O(4) bond length is 2.34 Å. The Er(1)-O(5) bond length is 2.29 Å. The Er(1)-O(6) bond length is 2.28 Å. C(1) is bonded in a distorted tetrahedral geometry to one P(1), one H(1), and one H(2) atom. The C(1)-P(1) bond length is 1.82 Å. The C(1)-H(1) bond length is 1.10 Å. The C(1)-H(2) bond length is 1.10 Å. P(1) is bonded to one C(1), one O(1), one O(2), and one O(3) atom to form PCO3 tetrahedra that share corners with three equivalent Er(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 15-36°. The P(1)-O(1) bond length is 1.53 Å. The P(1)-O(2) bond length is 1.54 Å. The P(1)-O(3) bond length is 1.54 Å. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one C(1) atom. In the second H site, H(2) is bonded in a single-bond geometry to one C(1) atom. S(1) is bonded in a distorted trigonal non-coplanar geometry to one O(4), one O(5), and one O(6) atom. The S(1)-O(4) bond length is 1.48 Å. The S(1)-O(5) bond length is 1.47 Å. The S(1)-O(6) bond length is 1.47 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to one Er(1) and one P(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Er(1) and one P(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Er(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Er(1) and one S(1) atom. In the fifth O site, O(5) is bonded in a linear geometry to one Er(1) and one S(1) atom. In the sixth O site, O(6) is bonded in a linear geometry to one Er(1) and one S(1) atom. Linkers: 2 [O]P([O])(=O)CCS([O])([O])[O]. Metal clusters: 2 [Er]. RCSR code: sql. The MOF has largest included sphere 1.96 A, density 3.26 g/cm3, surface area 1937.78 m2/g, accessible volume 0.05 cm3/g