Free energy mode
P5Grand can calculate the free energy of a system at a given temperature.
The basic command to calculate free energy is
$ python /dir/to/P5Grand/__main__.py CEL.log -calc f
or
$ python /dir/to/P5Grand CEL.log -calc f
If the name of input file is CEL.log, it is not essential to write CEL.log
The example files for testing the command is here. The log messages obtained from the example files is as follows:
DataFile: CEL.log
-strain : BM_constant.dat
-unit : eV
-calc : free_energy
-T : 300.0 K
-points : 32
Read CEL.log
Read BM_constant.dat
0.00000 0.000000
0.03125 0.001674
0.06250 0.004003
0.09375 0.006320
0.12500 0.008493
0.15625 0.010476
0.18750 0.012277
0.21875 0.013920
0.25000 0.015386
0.28125 0.016765
0.31250 0.018161
0.34375 0.019448
0.37500 0.020529
0.40625 0.021405
0.43750 0.022186
0.46875 0.022806
0.50000 0.023155
0.53125 0.023316
0.56250 0.023382
0.59375 0.023344
0.62500 0.023003
0.65625 0.022341
0.68750 0.021498
0.71875 0.020451
0.75000 0.019163
0.78125 0.017695
0.81250 0.016021
0.84375 0.014063
0.87500 0.011771
0.90625 0.009123
0.93750 0.006132
0.96875 0.002883
1.00000 0.000000
options
-calc
-calc f | p | a
default : p
The option to choose what to be calculated.
f indicates free energy, p indicates phase diagram, and a indicates average property.
To calculate free energy,
-calc must be f.$ python /dir/to/P5Grand CEL.log -calc f
-strain
-strain [fileName]
default : BM_constant.dat
The option to select the fitting equation for strain energy.
$ python /dir/to/P5Grand CEL.log -calc f -strain BM_constant.dat
-unit
-unit eV | J
default : eV
The option to select energy unit of input file and strain energy.
$ python /dir/to/P5Grand CEL.log -calc f -unit eV
-T
-T [real >0]
default : 300
unit : Kelvin
Target temperature to be calculated.
$ python /dir/to/P5Grand CEL.log -calc f -T 500
-points
-points [integer > 1]
default : 32
The number of calculated compositions -1. The composition interval is set as 1/[int]
$ python /dir/to/P5Grand CEL.log -calc f -points 50