Simple Lattice Simulation of Chiral Discrimination in Monolayers

A simulation method based on cellular automata on a hexagonal lattice is applied to model the behavior of chiral molecules on a surface, such as those in a monolayer of amphiphiles each having a single chiral center. The simulation method includes movement and orientation rules, with the objects (“molecules”) on the lattice vertices possessing three different groups with one group pointing along each edge. Periodic boundary conditions are employed in the simulations. Interaction strengths are calculated between pairs of groups occupying the edges between vertices and summed for the entire system. The model successfully reproduces the formation of domains as a consequence of the movement rule. The movement rule can be adjusted to simulate homochiral discrimination or heterochiral discrimination for the case of racemic mixtures. The orientation rule results in a preference for orientations of the molecules that minimize the total interaction strength.