Pivot Methods for Global Optimizations.
The pivot method for global optimization is based on pivot moves through phase space.
We begin by assuming a continuous
phase space S.
Within phase space is defined a real function f(vec{x}).
Our goal is to determine the global
minimum value of this function within the defined
phase space.
Briefly,
we start with N=2m initial probes, of which m
probes will act as the pivot probes, and the remaining m
probes will be relocated.
A local selection of the m pivot probes begins with a search at
each probe for its nearest neighbor, based on the distance of the
probes.
Once we have paired the probes,
the probe with the lower value for the function f(vec{x})
is defined as the pivot probe, the other probe being the probe
that will be relocated.
For each pivot probe with parameter values vec{x}{B,i}, we
explore phase space by placing the probe to be relocated near
the pivot probe by changing its parameters
according to a general q-distribution
based on the Tsallis
entropy
for the placement of the probes near the pivot probes.
The method quickly converges,
does not require derivatives, and is resistant to becoming trapped in local minima.
A New Approach to Global
Minimization, A. Stanton, R. Bleil and S. Kais,
J. Comp. Chem. 18, 594-599 (1997).
Pivot Method for Global
Optimization, P. Serra. A.F. Stanton and S. Kais,
Phys. Rev. E 55, 1162-1165 (1997).
Comparison
Study of Pivot Methods for Global Optimization, P. Serra, A.F. Stanton, S. Kais and R. Bleil,
J.
Chem. Phys. 106, 7170-7177 (1997).
Symmetry Breaking and Stability of Binary Clusters",Pablo Serra and Sabre Kais,
Chem. Phys. Letters 275, 211-214 (1997).
Pivot methods for global optimization: A study of water clusters N=2,...,33
", Pablo Nigra and Sabre Kais, Chem. Phys. Letters,
305, 433-438 (1999).
Study of phase changes in water octamer using the parallel
tempering and multihistogram methods", Pablo Nigra, Marcelo Carignano and Sabre Kais,"
J. Chem. Phys. 115, 2621-2628 (2001).