Rotational diffusion of uniaxial probes in biaxial liquid crystal phases
نویسنده
چکیده
We discuss the reorientation of a cylindrically symmetric probe in a biaxial orthorombic medium, such as a biaxial nematic. We write down and solve for the first time the rotational diffusion equation for a rod-like or disc-like uniaxial probe reorienting in a medium of biaxial symmetry. We calculate first and second rank correlation functions both in the uniaxial and biaxial phase, giving the possibility of following the evolution of dynamic observables of interest (e.g. spectral densities) through the uniaxial-biaxial phase transition. Nonperturbative and approximate analytical solutions are provided.
منابع مشابه
Rototranslational diffusion of biaxial probes in uniaxial liquid crystal phases
We discuss the problem of rototranslational diffusion of a rigid biaxial molecule dissolved in a uniaxial smectic liquid crystal phase. We examine distorted rod and disk like molecules and show how biaxiality and rototranslational coupling can produce significant effects on some of the correlation functions and spectral densities most useful in analyzing experimental observables.
متن کاملRotational diffusion of biaxial probes in biaxial liquid crystal phases, Mol. Phys., 85, 299-333 (1995)
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