Charge Density Analysis of Ferulic Acid: Robustness of a Trifurcated C–H···O Hydrogen Bond

Abstract

The toplogical features of a sporadic trifurcated C–H···O interaction region, where an oxygen atom acts as an acceptor of three weak hydrogen bonds, has been investigated by experimental and theoretical charge density analysis of ferulic acid. The interaction energy of the asymmetric molecular dimer formed by the trifurcated C–H···O motif, based on the multipolar model, is shown to be greater than the corresponding asymmetric O–H···O dimer in this crystal structure. Further, the hydrogen bond energies associated with these interaction motifs have been estimated from the local kinetic and potential energy densities at the bond critical points. The trends suggest that the interaction energy of the trifurcated C–H···O region is comparable to that of a single O–H···O hydrogen bond.