Variational approach to exciton transport in molecular crystals
نویسندگان
چکیده
The variational results for the free energy of an interacting exciton phonon system are used to derive expressions for the scattering rate and diffusion constant of an exciton in such a system. These expressions are applicable to both wide and narrow band cases, and includes the possibility of an abrupt transition from wide band (free) exciton to narrow band (localized) exciton. Some comments are made on the possibility of observing this transition by thermal modulation spectroscopy.
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