Starting from the DFT-optimised structure 1cp-sim, a series of a/b axes parameters, from 9.485 Å to 13.485 Å, was selected. Partial unit cell optimisations, i.e. only allowing the c axis parameter to relax while keeping the a/b cell parameters fixed during the optimisation, were performed. From this, a series of structural models of 1, named 1sim (a = x) where x = the fixed a axis parameter, with unit cell volumes ranging from 1213 Å 3 to 2126 Å 3 , was generated and used to predict powder X-ray diffractograms as 1 closes. Qualitative comparison of powder X-ray diffractograms (Figure ) suggest that samples of 1as dried from both EtOH and MeCN form the most closed structures, with unit cell volumes of approximately 1600 Å 3 (a tentative Pawley refinement for a sample dried from EtOH gives a unit cell volume of 1618 Å 3 , SI Figure ) which are at intermediate levels of closure compared to 1cp-sim. H NMR spectroscopic analysis of digested samples (SI, Figure ) shows the attempted solvent exchanges do not successfully remove all residual DMF from the pores of 1 which we believe results in intermediate phases being accessed.