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Parameters
Following is a complete list of all potfit parameters, together with a short description of their meaning, and indications when they are needed. Floating point numbers should be given in decimal notation. Vectors are given as a list of components, separated by spaces or tabs (all on one line). An asterisk marks required parameters.
The first column contains the name of the parameter, the second the type of the parameter and the third one the initial value (if there is one). The second line is a short explanation for the parameter
main parameters
ntypes* - integer - (none)
<html> </html>number of atom types (types vary in [0,..,ntypes-1])
file names
config* - string - (none)
<html> </html>file with atom configuration in force format, see Configurations
startpot* - string - (none)
<html> </html>file name for starting potential, see Potential_files
tempfile* - string - (none)
<html> </html>file name for temporary (intermediate) potential, see Tempfile
endpot - string - $startpot_end
<html> </html>file name for final potential, see Potential_files
imdpot - string - (none)
<html> </html>file name prefix for imd potentials, see IMD
plotfile - string - (none)
<html> </html>file name for plotting potential, see Plotfile
flagfile - string - (none)
<html> </html>file whose presence terminates fit, see Flagfile
general options
write_pair - boolean - 0
<html> </html>write radial pair distribution, see Pair_distribution
write_lammps - boolean - 0
<html> </html>write potential in LAMMPS format, see Lammps
Minimization options
opt - boolean - 0
<html> </html>whether or not to perform an optimization
eng_weight* - float - (none)
<html> </html>weight of energy in minimization, see Algorithms
stress_weight (* if compiled with stress) - float - (none)
<html> </html>weight of stress in minimiziation, see Algorithms
anneal_temp - float - 1.
<html> </html>starting temperature for simulated annealing, set to 0 to skip simulated annealing, see Simulated Annealing
evo_threshold - float - 1.
<html> </html>stop the evolutionary algorithm if the difference in the population is smaller than this, set to zero to skip evo, see Differential Evolution
d_eps - float - 0.0
<html> </html>error margin for powell minimization - if the improvement is smaller, the optimization is stopped, see Method of Least Squares
seed - integer - 4
<html> </html>seed for random number generator
apot_punish - float - 0.
<html> </html>scaling factor for apot punishments, this does not affect out-of-bounds punishment, see potentials/Punishments
options only for tabulated potentials
plotpointfile* - string - (none)
<html> </html>file name for plotting the sampling points, see Plotpointfile
distfile - string - (none)
<html> </html>file name for distribution file (* with compile option 'dist'), see Distfile
maxchfile - string - (none)
<html> </html>file with maximal permissible changes for each parameter, see Maxchfile
options only for analytic potentials
plotmin - float - 0.0
<html> </html>starting point for plotting potentials, see Plotfile
enable_cp - boolean - 0
<html> </html>whether or not to include chemical potentials, see Potentials
options for output
imdpotsteps - integer - 1000
<html> </html>number of points in each function in imd and lammps potential files, see IMD / Lammps
output_prefix - string - (none)
<html> </html>prefix for various output files, see Output
extend - float - 2.
<html> </html>how many steps should the imd potentials be extrapolated, see IMD
parameter for option coulomb
dp_cut - float - 10
<html> </html>cutoff-radius for electrostatic interactions, doesn't depend on other pair-function-radii.
parameters for option dipole
dp_tol - float - 1.e-7
<html> </html>dipole iteration precision.
dp_mix - float - 0.2
<html> </html>mixing parameter for dipole convergence during iteration.