Powder X-ray diffraction (PXRD). Samples were measured on a Bruker D8 advanced diffractometer (Cu Kα radiation λ = 1.518 Å) equipped with a position sensitive LynxEye detector with Bragg-Brentano parafocusing geometry at room temperature. Samples were packed into 5 mm discs on low background silicon substrates. Pawley refinement of crystalline ZIF-62 was performed using the crystallographic information file of ZIF-62 and Topas academic software version 7.2. Differential Scanning Calorimetry (DSC). DSC measurements were taken using a NETSCH DSC 214 Polyma instrument, using an empty aluminium crucible as the reference. Background corrections were performed for all measurements using an empty aluminium pan on the same heating cycle. Approximately 5 mg of each sample was loaded into an aluminium crucible (30 µL) with a pierced lid under argon and heated at a rate of 10 °C/min. Glass transition temperatures (Tg) were obtained during the second DSC upscan and corresponded to the mid-point of the change in gradient of the heat flow signal. Simultaneous DSC-TGA. TGA traces of all samples were recorded using a TA instruments Q-650 series DSC and the data analysed using TA Universal Analysis software. Approximately 5-10 mg of each sample was placed in open alumina crucibles and heated at 10 °C/min under argon.