Electronic Resource
College Park, Md.
:
American Institute of Physics (AIP)
The Journal of Chemical Physics
97 (1992), S. 1296-1305
ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
We consider the relaxation and equilibration of an excitation in a trimer coupled to a phonon bath. Energy transfer within the trimer occurs via resonance interactions and the coupling between the trimer and the phonon bath occurs via the modulation of the monomer energies by the phonons. The problem is dealt with fully quantum mechanically. We focus on the effects of certain forms of bond disorder, in particular, on the effects of two different resonance interactions in a trimer of otherwise identical monomers. We find that "bond disorder'' even unaccompanied by "site disorder'' leads to spontaneous energy localization. This result would not be predicted by semiclassical master equation models or even by most stochastic Liouville equation models−it requires the proper (finite temperature) quantum analysis not only of the trimer system but also of the heat bath. Indeed, a nonuniform distribution of energy among the monomers is a necessary consequence of the proper thermal distribution of populations among the eigenstates of the trimer. We also discuss the relaxation of the trimer when the highest energy level of the trimer is initially excited. We find that the decay of the highest level and the population of the lowest level proceed monotonically, but the intermediate energy level in general has a "population overshoot'' before achieving equilibrium. Correspondingly, the populations of the various monomers go to equilibrium in a nonmonotonic way.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.463256
| Library |
Location |
Call Number |
Volume/Issue/Year |
Availability |
