C. Micheletti, A. Laio and M. Parrinello
Reconstructing the Density of States by History-Dependent
Phys. Rev. Lett. 92 170601 (2004).
Preprint full text (cond-mat archive).
Link to online article.
We present a novel method for the calculation of the energy density of
states D(E) for systems described by classical statistical
mechanics. The method builds on an extension of a recently proposed
strategy that allows the free energy profile of a canonical system to
be recovered within a pre-assigned accuracy,[A. Laio and
M. Parrinello, PNAS 2002]. The method allows a good control over the
error on the recovered system entropy. This fact is exploited to
obtain D(E) more efficiently by combining measurements at different
temperatures. The accuracy and efficiency of the method are tested for
the two-dimensional Ising model (up to size 50x50) by comparison with
both exact results and previous studies. This method is a general one
and should be applicable to more realistic model systems.