Figure 3 . Spin density plots of 1,2-diBeX and 1,2-diZnX radical anions. Bond stretch isomers of 1,2-diBeX radical anions are shown in the middle column. Contour value used in 0.03.
We then turned our attention to investigate the electronic structure of the studied systems. For this, we performed quantum theory of atoms in molecules (QTAIM),18 electron localization function (ELF)19 and natural bonding orbital (NBO) analyses.15 Table 1 contains the numerical values.
Table 1 . Electron density at the Be-Be and Zn-Zn bond critical points (ρ ), laplacian of electron density (∇2ρ ), local electronic energy density, ELF population of the Be-Be and Zn-Zn bonds V(M,M), NBO populations of Be-Be and Zn-Zn bonds and hybridization of the Be-Be and Zn-Zn bond. All values are in a.u.