For the four crystal structures considered: MFU-4l, KHCO 3 (s), and KHCO 3 -CD-MOF, individual convergence for NMR parameter calculations of cut-off energy (E cut ) and Monkhorst-Pack k-point grid spacing were performed. For MFU-4l (both CO 2 binding modes used the same parameters), an E cut = 650 eV and k-point spacing = 0.04 Å-1 (grid = 2 2 2) were used giving convergence within σ iso = 0.5 ppm, C Q = 0.01 MHz and η Q = 0.002 (the values given are root-mean-squared average parameter difference, across all oxygen atoms, between the chosen E cut /k-point spacing and the subsequent higher accuracy cut-off/spacing of the convergence test.