Fig. 4: Electronic nature of 1a, 1b, A, and B determined by DFT calculations at the M06-2X/6-311G(d,p) level of theory.

a Plots of the HOMO and the LUMO of 1a, 1b, A, and B. Hydrogen atoms are omitted for clarity (isosurface value = 0.03). b Plot of the Laplacian of the electron density on the Ga1Ga2Ga2’Ga1’ plane with bond paths (brown lines) and BCPs (blue dots) in 1a.