To simulate and help interpret the nature of the newly synthesized Ga2R2Na2 molecule with bulky groups, ab initio and density functional quantum mechanical methods were applied to study the structures and bonding of the model [HGaGaH](2-), [H2GaGaH2](2-), and [H3CGaGaCH3](2-) dianions, as well as the neutral Na-2[H2GaGaH2], Na-2[H3CGaGaCH3], Ga2H2, and Ga2H3 species. Basis sets of triple-zeta plus double polarization quality augmented with diffuse functions were employed. No general bond length-bond order relationship is found. Bending from linearity of the acetylene analogues increases the GaGa separation more than the bond order is decreased. The GaGa bonding in the experimental molecule is concluded to be between triple and double in character despite the relatively long bond length.