Minima hopping

job = global_optimization is minima hopping. It is a different job from basin hopping. The client logs Beginning minima hopping and reads pos.con. It writes monitoring.dat and earr.dat in the working directory.

[Global Optimization] move_method is md (the default) or random. The molecular-dynamics move is a constant-energy trajectory. It stops after mdmin potential-energy minima (default 3) or after 1000 steps. The random move uses [Basin Hopping] displacement (default 0.5, in the length unit of the positions) and that section’s displacement_distribution.

decision_method is the non-probabilistic energy window (npew, the default) or boltzmann. Any other value stops the client while the file is read. npew accepts a hop whose energy is below the current energy plus a window. The window starts at 0.1 eV. An acceptance multiplies it by 1/alpha, and a rejection multiplies it by alpha. alpha defaults to 1.02. boltzmann keeps an uphill hop with probability exp(-de/(kB*temperature)) at [Main] temperature. A temperature or kB that is not positive rejects that hop.

beta (default 1.05) scales the kinetic energy of the next molecular-dynamics escape. A repeat of the current minimum, or a minimum already in the list, multiplies it by beta. A new minimum multiplies it by 1/beta. steps (default 10000) is the number of hops. The loop also stops when the current energy falls below target_energy.

[Main]
job = global_optimization
temperature = 300

[Global Optimization]
move_method = md
decision_method = npew
steps = 10000
beta = 1.05
alpha = 1.02
mdmin = 3