A quantum chemical analysis of the intermolecular interactions between the molecules of the typically aprotic, dipolar acetone

Quantum chemical calculations have been performed on acetone dimers at the second-order Møller-Plesset level and employing density functional theory. The most stable dimer, comparable in stability to the water dimer at the MP2 level, is stabilized in antiparallel stacked orientation by a fine interplay of intermolecular interactions including the electrostatic attraction between the antiparallel carbonyl groups, four CH … O interactions and steric repulsion. The examination of mixed dimers in a similar arrangement of formaldehyde, acetaldehyde and acetone makes it possible to estimate the contributions from the different types of interactions to the overall stabilization of the dimers.