Table 2.

The characteristics of the bond critical point (in au) corresponding to the bond path linking the Z-center with the π-electron system; the electron density at BCP, ρ_BCP, its laplacian, ∇²ρ_BCP, and the total electron energy density at BCP, H_BCP.

Complex	ρBCP	∇2ρBCP	HBCP
AlBr3-C2H2	0.0276	0.0818	−0.0035
AlBr3-C2H4	0.0292	0.0725	−0.0049
AlCl3-C2H2	0.0272	0.0847	−0.0031
AlCl3-C2H4	0.0284	0.0735	−0.0044
AlF3-C2H2	0.0275	0.1036	−0.0017
AlF3-C2H4	0.0283	0.0903	−0.0030
AlH3-C2H2	0.0212	0.0683	−0.0014
AlH3-C2H4	0.0234	0.0687	−0.0023
BBr3-C2H2	0.0068	0.0191	0.0008
BBr3-C2H4	0.0073	0.0195	0.0007
BCl3-C2H2	0.0064	0.0183	0.0007
BCl3-C2H4	0.0070	0.0182	0.0007
BF3-C2H2	0.0092	0.0273	0.0010
BF3-C2H4	0.0101	0.0264	0.0008
BH3-C2H2	0.0620	0.0325	−0.0392