Our results show that static disorder is the major contributor to the reduction in the bandgap; however, it alone can not account for the total reduction in the size of the bandgap. During the molecular dynamics simulation, which investigated dynamic disorder in Sn 2 SbS 2 I 3 , the bandgap was found to fluctuate by up to ± 0.175 eV. The fluctuations, in combination with changes to the electronic structure driven by sample inhomogeneity from the solution synthesis, may reduce the bandgap further. The results demonstrate the sensitivity of the electronic bandgap to static cation disorder in these materials, potentially allowing for the optimisation of the material properties for photovoltaic operations. Cation disorder can be induced at relatively low temperatures (for example compared to the widely-investigated II-IV-N 2 nitrides with typical order-disorder transitions in the range 2000-3000 K), allowing for disorder engineering under less energyintensive conditions. To study what factors are contributing to the change in the bandgap, we calculated the inverse participation ratio (IPR) of the electronic states in 1024-atom supercells matching the cluster vectors obtained from the MC simulations between 0-700 K. The IPR is obtained from the local density of states,