Electride Characteristics of Some Binuclear Sandwich Complexes of Alkaline Earth Metals, M(η-L) (M = Be, Mg; L = CH, N, P, As).

calculations have been performed for a series of binuclear sandwich complexes, M(η-L). It has been observed that the eclipsed and staggered conformations have almost equal amount of energies. The M-M bond lengths are comparable with those in the free M molecules (M = Be, Mg). The nuclear-independent chemical shift (NICS) values indicate the aromaticity of these complexes. The stability of Be(η-L) complexes is higher than that of the Mg(η-L) complexes. The natural bond orbital (NBO) analysis and electron density descriptors proved the existence of a single covalent M-M bond in an M fragment. It has been observed that each M-M bond contains a non-nuclear attractor (NNA) at the center of the respective bond. The Laplacian of electron density [∇ρ()] is negative at the NNAs. The energy decomposition analysis (EDA) showed that M and 2L represent the bonding interaction in the complexes. All of the designed binuclear sandwich complexes behave as electrides.