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Volume 129, Issue 9, 07 September 2008
129(2008); http://dx.doi.org/10.1063/1.2978949View Description Hide Description
The Jarzynski equality (JE) and the undergirding Crooks fluctuation theorem (CFT) have generated intense interest recently among researchers in physical and biological sciences. It has been held that the CFT has wider applicability than the JE. This note shows that the two are equally applicable and that their applicability is possibly limited to near-equilibrium processes, where the linear fluctuation-dissipation theorem holds.
Optical absorption spectra and monomer interaction in polymers: Investigation of exciton coupling in DNA hairpins129(2008); http://dx.doi.org/10.1063/1.2977727View Description Hide Description
We investigate the effect of exciton coupling on the optical absorptionspectra of polymer molecules under conditions of strong inhomogeneous broadening. It is shown that the dependence of the maximum in the rescaled absorptionspectrum on the number of monomers is determined by their resonant exciton coupling and is insensitive to inhomogeneous broadening. Thus the absorptionspectrum can be used to determine optical interactions between monomers. Using our theory and semiempirical calculations we determine exciton coupling between adjacent AT pairs in DNA to be 0.04 eV and discuss exciton localization in DNA hairpins composed of AT pairs.