Impact of steric interactions on the helical transition in assemblies of discotic molecules.
We investigate theoretically the effect of excluded-volume interactions on the helical configurational transition of supramolecular assemblies in solutions of chiral disklike molecules. To this end, we set up a second-virial theory within the context of the helical self-assembly of rodlike objects. We find that interaggregate interactions shift both the helical-transition point and the sharpness of the transition. For realistic values of the model parameters, the helical-transition temperature shifts by several degrees, and the more so the higher the concentration of assembling material. The mean aggregation number is also affected by the interactions, albeit only by a modest amount, unless the solution becomes very concentrated.
van Gestel
Jeroen
J
Physical Chemistry and Molecular Thermodynamics Group, Technische Universiteit Delft, 2600 GA Delft, The Netherlands. J.VanGrestel@tnw.tudelft.nl
van der Schoot
Paul
P