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C. David Sherrill coauthored electronic-structure calculations of the benzene dimer. The work compares T-shaped and parallel-displaced arrangements and estimates their interaction energies near the computational basis-set limit.

Two aromatic molecules need not favour a perfectly face-centred stack. Comparing several geometries with electron-correlation methods helps distinguish the effects of electrostatics and dispersion in a noncovalent contact.^[ref]

Edward F. Valeev coauthored calculations of benzene dimer interaction energies using correlated electronic-structure methods. The study compares T-shaped and parallel-displaced minima while examining convergence toward the computational limit.

A small interaction energy can be sensitive to the treatment of electron correlation and to the available basis functions. Assessing convergence is therefore part of the physical interpretation, rather than only a numerical convenience.^[ref]

Mutasem Omar Sinnokrot coauthored research on benzene dimer.^[ref]

Two benzene molecules associated by dispersion and electrostatic interactions. T-shaped and parallel-displaced geometries are important low-energy arrangements; a single permanent dipole–dipole model is inadequate.

water achieves substantial binding through a localized O–H···O hydrogen bond; benzene achieves a comparable total through a larger set of weaker contacts. In the water dimer, one water is the hydrogen-bond donor and the other presents an oxygen lone pair region as acceptor. The interaction includes electrostatics, induction interaction, dispersion and short-range exchange repulsion; a hydrogen bond is not a separate fundamental force that can simply be added to all those terms again.

For benzene, draw a T-shaped edge-to-face pair or a slipped parallel pair. Its larger, more polarizable electron clouds provide appreciable London dispersion. Its quadrupolar charge distribution also makes the energy orientation dependent, despite each molecule having no permanent dipole by symmetry. An edge C–H approaching the other ring's pi region is therefore preferable to a model of two structureless, noninteracting dipole-free objects. Dispersion attracts while Pauli repulsion limits close overlap. Several distributed contacts can sum to the scale of one water–water hydrogen bond; counting only the number of conventional hydrogen bonds would miss them.

The comparison concerns the given gas-phase pair interaction energies, not an equality of every solvent-dependent association free energy. Correlated primary calculations explicitly identify both T-shaped and parallel-displaced benzene-dimer minima, rather than a uniquely preferred perfectly eclipsed sandwich.^[ref]