In-house powder X ray diffraction (PXRD) measurements were carried out using a Panalytical X'pert Pro diffractometer (Cu Kα1,2, λ1 = 1.540598 Å, λ2 = 1.544426 Å) using a Bragg-Brentano geometry (Supplementary Fig. ). Variable-temperature PXRD measurements were carried out using a Bruker D8 Discover diffractometer, equipped with an Anton Paar XRK 900 reaction chamber (Supplementary Fig. ). Thermogravimetric analysis (TGA) data (Supplementary Fig. ) of as-synthesized MOFs were collected using a Perkin Elmer TGA 7. SU-106 and SU-111 were not fully characterized for stability tests nor was ion exchange performed as these phases were obtained as phase mixtures.