Substitution of sub-molecular structure can alter surface anchoring of liquid crystals: Impact of cyclohexyl vs phenyl groups on surface anchoring of nematic LC

In the design for responsive and functional materials, the ability to explain their macroscopic behavior from the nanoscale structure of their components is a still challenging but promising approach. Here we demonstrate experimentally that the macroscopic orientational ordering of a liquid crystal (LC) in its interaction with perfluoroalkane oils can be altered by the substitution of sub-molecular structures from phenyl to alkyl rings. Using molecular dynamics simulations and enhanced sampling methods, we can reconstruct the LC interface with perfluoroalkane oils. Based on compartmentalization of the mesogens and potential of mean force between each compartment and fluorocarbon molecules, we provide an explicit explanation of the formation of molecular ordering where affinity between perfluorocarbons and cyclohexyl group is favored over phenyl groups.