N-heterocyclic carbene-stabilized homoatomic lithium(0) complexes with a lithium–lithium covalent bond: A theoretical design and characterization.

Density functional theory calculations (B3LYP and B2PLYP-D2) have been utilized to design and characterize novel homoatomic lithium(0) organometallic complexes of the NHC → Li–Li ← NHC type (NHC = N-heterocyclic carbenes). The computed Li–Li bond length and energy are consistent with those experimentally observed for Li 2 (g). These and other structural and energetic data suggest that such organolithium compounds should be viable targets for synthesis. These compounds would represent a new class of molecular “allotropes” and could have novel reactivities. [ABSTRACT FROM AUTHOR]