Enhancement effect of lithium bonding on the strength of π -hole interactions in O 2 S···NCLi···NCX and O 2 S···CNLi···CNX complexes (X = H, F, CN, OH and CH 3

These positive regions can interact in a highly directional manner with any negative site, thereby giving rise to a directional interaction. This type of interaction is labelled as ‘π-hole’ bonding.

In this study, ab initio calculations are performed to study the cooperativity effects between the π-hole bond and lithium bond interactions in O 2 S···NCLi···NCX and O 2 S···CNLi···CNX complexes, where X = H, F, CN, OH and CH 3 . These effects are investigated in terms of geometric and energetic features of the complexes, which are computed by the MP2/aug-cc-pVTZ method. Cooperative effects are found when S···N(C) and Li···N(C) bonds coexist in the same complex.