This is an old revision of the document!
toc_right
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) :number of atom types (types vary in [0,..,ntypes-1])
file names
;config* - string - (none) :file with atom configuration in force format, see Configurations ;startpot* - string - (none) :file name for starting potential, see Potential_files ;tempfile* - string - (none) :file name for temporary (intermediate) potential, see Tempfile ;endpot - string - $startpot_end :file name for final potential, see Potential_files ;imdpot - string - (none) :file name prefix for imd potentials, see IMD ;plotfile - string - (none) :file name for plotting potential, see Plotfile ;flagfile - string - (none) :file whose presence terminates fit, see Flagfile
general options
;write_pair - boolean - 0 :write radial pair distribution, see Pair_distribution ;write_lammps - boolean - 0 :write potential in LAMMPS format, see Lammps
Minimization options
;opt - boolean - 0 :whether or not to perform an optimization ;eng_weight* - float - (none) :weight of energy in minimization, see Algorithms ;stress_weight (* if compiled with <tt>stress</tt>) - float - (none) :weight of stress in minimiziation, see Algorithms ;anneal_temp - float - 1. :starting temperature for simulated annealing, set to 0 to skip simulated annealing, see Simulated Annealing ;evo_threshold - float - 1. :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 :error margin for powell minimization - if the improvement is smaller, the optimization is stopped, see Method of Least Squares ;seed - integer - 4 :seed for random number generator ;apot_punish - float - 0. :scaling factor for apot punishments, this does not affect out-of-bounds punishment, see Analytic potentials/Punishments
options only for tabulated potentials
;plotpointfile* - string - (none) :file name for plotting the sampling points, see Plotpointfile ;distfile - string - (none) :file name for distribution file (* with compile option 'dist'), see Distfile ;maxchfile - string - (none) :file with maximal permissible changes for each parameter, see Maxchfile
options only for analytic potentials
;plotmin - float - 0.0 :starting point for plotting potentials, see Plotfile ;enable_cp - boolean - 0 :whether or not to include chemical potentials, see Pair Potentials
options for output
;imdpotsteps - integer - 1000 :number of points in each function in imd and lammps potential files, see IMD / Lammps ;output_prefix - string - (none) :prefix for various output files, see Output ;extend - float - 2. :how many steps should the imd potentials be extrapolated, see IMD
parameter for option [[Coulomb|coulomb]]
;dp_cut - float - 10 :cutoff-radius for electrostatic interactions, doesn't depend on other pair-function-radii.
parameters for option [[Dipole|dipole]]
;dp_tol - float - 1.e-7 :dipole iteration precision. ;dp_mix - float - 0.2 :mixing parameter for dipole convergence during iteration.