Theoretical Study on Interactions between N-Butylpyridinium Nitrate and Thiophenic Compounds

By using density functional theory calculations, we have performed a systemic study on the electronic structures and topological properties of interactions between N-butylpyridinium nitrate ([BPY](+)[NO3](-)) and thiophene (TS), benzothiophene (BT), dibenzothiophene (DBT), naphthalene (NAP). The most stable structure of [BPY](+)[NO3](-) ion pair indicates that hydrogen bonding interactions between oxygen atoms on [NO3](-) anion and C2-H2 on pyridinium ring play a dominating role in the formation of ion pair. The occurrence of hydrogen bonding,pi center dot center dot center dot H-C, and pi...pi interactions between [BPY](+)[NO3](-) and TS, BT, DBT, NAP has been corroborated at the molecular level. But hydrogen bonding and pi...pi interactions between [BPY](+)[NO3](-) and NAP are weak in terms of structural properties and NBO, AIM analyses. DBT is prior to adsorption on N-butylpyridinium nitrate ionic liquid.