The resulting curves E g = E g (V ) allow the extraction of volume deformation potentials Ξ, which are listed for standard DFT and DFT+A-1 ⁄2 methods and compared with reference data in Table for both direct and indirect gaps. These values were computed by analyzing the variations in the band edges (VBM and CBM) relative to changes in equilibrium volume V 0 . The energy fluctuations were assessed by varying the volume from 96% V 0 to 104% V 0 in 2% increments. The obtained absolute values are comparable to those reported for other ionic Ga and In compounds, with only slight variations among polymorphs of the same oxide. However, the average difference between the deformation potentials of Ga 2 O 3 and