The orientational ordering of solute molecules in nematic solvents: cyanobenzenes, bromobenzenes, and p-benzoquinone in EBBA and 1132

Abstract

The orientational order parameters of benzonitrile and o-, m-, and p-dicyanobenzene, monobromo- and p-dibromobenzene, and p-benzoquinone, dissolved in two nematic solvents, 1132 and EBBA, have been measured as functions of temperature, and used to determine the potential energy parameters for each solute–solvent pair. These parameters have been correlated with a short-range interaction based upon a shape and size function of the solute molecule and a long-range contribution due to the interaction between the solute molecular quadrupole moment and the average electric field gradient. Keywords: nematic liquid crystals, orientational ordering of solutes.