Abstract
It is shown that the fraction of imaginary-frequency instantaneous normal modes (INM) may be defined and calculated in a random energy model (REM) of liquids. The configurational entropy and the averaged hopping rate among the states, R, are also obtained and related to with the results and The proportionality between R and is the basis of existing INM theories of diffusion, so the REM further confirms their validity. A link to opens new avenues for introducing INM into dynamical theories. Liquid states are usually defined by assigning a configuration to the minimum to which it will drain, but the REM naturally treats saddle barriers on the same footing as minima, which may be a better mapping of the continuum of configurations to discrete states. Requirements for a detailed REM description of liquids are discussed.
- Received 7 February 2000
DOI:https://doi.org/10.1103/PhysRevE.62.7905
©2000 American Physical Society