Computations were performed with the CP2K program package implying a mixed Gaussian and plane waves framework. Starting from the experimental crystal structures of MFU-4 (CCDC723714) and MFU-4-Br (this work), the unit cell geometries were optimised using the PBEsol functional, DFT-D3 van der Waals pair potential to account for dispersion contributions, DZVP-MOLOPT-SR basis set, the Goedecker-Teter-Hutter pseudopotentials and applying the Broyden-Fletcher-Goldfarb-Shanno (BFGS) algorithm within a threshold of 1x10 -6 hartree in the energy and 4.5x10 -4 hartree/bohr in the forces. For all calculations, a grid cutoff / relative grid cutoff of 900/80 Ry was used. Input and relevant data files for the computational results presented in this manuscript are available on .