The structure of CuBiSeCl2 was relaxed until forces fell below 0.01 eV Å -1 with a Γpoint centred 10×5×3 k-point grid. The high-symmetry path for calculation of the band structure was obtained using the Automatic Flow (AFLOW) library. Cu + and Bi 3+ are displaced from the centre of their respective octahedral / polyhedral environment, visible in Figure . Cu is displaced in the direction of the Cl-Cl octahedral edge to achieve sufficient valence. Bi is then displaced in the direction of the now under-bonded Cl -at the octahedral corner. The origin of these displacements can be understood through comparisons with known compounds that exhibit similar structures: MnBiSe2Br (Pnma) and CuBiSCl2 (Cmcm).