Structure and property of the furan dimer (C4H4O)(2): a theoretical study

Abstract Furan dimer (C 4 H 4 O) 2 was subjected to density functional theory (DFT). Four equilibrium isomers were located, and the most stable isomer has two strong O⋯H–C hydrogen bonds which interactions are enhanced by the presence of the cooperation effect. The interaction energies were calculated and the effects of basis set superposition errors (BSSE) were systematically considered. The natural bond orbital (NBO) analysis was performed to understand better the nature of the corresponding intermolecular interactions. All the results indicate that I and II are formed via hydrogen-bonding interactions, and van der Waals interactions play a key role in the formation of III and IV.