The Computed lattice constants (a), cell volume (V), formation energy(ΔE_f), final enthalpy E_total (GaGeX₃), and energy gap (E_g) of GaGeX₃ (X = Cl, Br, and I).

Compound	a (Å)	V (Å3)	ΔEf (eV per atom)	E total (GaGeX3) (eV)	E g (eV) (PBE)	E g (eV) (HSE06)
GaGeCl3	5.220	142.277	−3.434	−5.9568 × 103	0.779	1.632
GaGeBr3	5.482	164.729	−3.106	−6.0788 × 103	0.462	1.284
GaGeI3	5.854	200.568	−2.750	−7.0753 × 103	0.330	1.140