Properties of uniaxial nematic liquid crystal of semiflexible even and odd dimers
نویسندگان
چکیده
A microscopic model is developed to describe statistical properties of a nematic phase consisting of semiflexible dimers. The effect of the spacer chain bonding the two mesogens is described by the local conditional probability in terms of a bare stiffness parameter Q +J EB /kT and a bare equilibrium angle bo between mesogenic monomers. In the framework of a molecular field approximation, taking into account long-range attraction and steric repulsion between monomers, we obtain a complete statistical description of the nematic phase with expressions for order parameter, mean-field potential, phase transition parameters and Frank elastic constants depending on details of spe&tic molecular structure. Comparison of results for dimers that are straight and bent in equilibrium and for corresponding monomers reveals the effect of molecular biaxiality and biaxial fluctuations.
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