Theoretical study on intermoiecular interactions between furan and dihalogen molecules XY(X,Y=F,Cl,Br)

摘要

Equilibrium geometries,interaction energies,atomic charge,and charge transfer for the intermoiecular interactions between furan and dihalogen molecules XY(X;Y=F,Cl,Br)were studied at the MP2/aug-cc-pVDZ level.Three types of geometry are observed in these interactions:the pi-type geometry(I),in which the XY lies above the furan ring and almost perpendicularly to the C4-C5 bond of furan;the sigma-type geometry(II),where the X atom is pointed toward the nonbonding electron pair(n pair)of oxygen atom in furan;and the chi-type geometry(III),describing a blueshift hydrogen bond formed between the hydrogen atom of furan and dihalogen molecules XY.The calculated interaction energies show that the pi-type structures are more stable than the corresponding sigma-type and chi-type structures.To study the nature of the intermoiecular interactions,an energy decomposition analysis was carried out and the results indicate that both the pi-type and sigma-type interactions are dominantly inductive energy in nature,while dispersion energy governs the chi-type interactions.