Mechanical Model of Rotation Frame for Phase Stability and Molecular Conformation in Liquid Crystal System

A mechanical model that explains the phase behaviors and thermal properties of a liquid crystal (LC) system is developed. We have modeled terphenyl liquid crystalline molecules on the basis of the architecture of a frame consisting of atomic nuclei. It is shown that the thermal stability of the LC molecules is dominated by the rotational dynamics of the nuclei frame. The characteristics of phase stability in a fluorine atom's position isomers in the terphenyl compounds are successfully interpreted with the use of an inertia tensor of the atom nuclei frame. From the observation of novel slim and fat isomers in fluorinated terphenyl LC compounds, we have developed a theory that interprets and predicts the thermal phase stability for novel isomeric LC compounds.