Half-Sandwich LaBn-/0 (n=14-17): π Dually Aromatic Lanthanide Boride Complexes with Multicenter Fluxional Bonds

Novel lanthanide boride complexes with unique structural and bonding patterns have been observed in recent experiments. Based on extensive first-principles theory calculations, we predict herein the possible existence of half-sandwich C-2v LaB14- (1), C-1 LaB15 (2), C-5v LaB16- (3), and C-s LaB17 (4) which all contain a La center coordinated by a bowl-like B-n ligand (n = 14-17). Detailed bonding analyses indicate that effective d-p coordination interactions exist between the La center and B-n ligand, making these half-sandwich complexes pi dually aromatic in nature. Energy decomposition analyses reveal that electrostatic (50.2%) and covalent (49.8%) interactions contribute almost equally to the overall attraction in LaB14- (1), with the La centre serving as both electron donor and acceptor. Molecular dynamics simulations show that both LaB14- (1) (La[B-4 (c) B-10](-)) and LaB17 (4) (La[B (c) B-5 (c) B-11]) with multicenter fluxional bonds behave like Wankel motors at finite temperatures.

Automated summary

Novel lanthanide boride complexes with unique structural and bonding patterns have been observed in recent experiments. Theoretical calculations predict the possible existence of various half-sandwich lanthanide boride complexes, which exhibit complex coordination interactions and pi dually aromatic nature. Molecular dynamics simulations show that these complexes behave like Wankel motors at finite temperatures.