Files Required

Several files must be provided to the program. They must all be contained in a data subfolder whose name should be specified as an input datum when the program is started (see the read_file function).

Mandatory files:

  1. A volume* v.s. *static energy file: this file contains only two columns; the first one lists unit cell volumes (in A^3); the second one lists static energies (in a.u.). The name of this file must be written in the Input file under the STATIC keyword

  2. A volume file listing the unit cell volumes (in A^3) at which vibrational frequencies of the normal modes were computed. The name of this file must be written in the Input file, under the VOLUME keyword

  3. A frequencies file: it consists of several columns and, precisely, one for each volume listed in the volume file; each column lists the set of frequencies computed at each volume. Frequencies must be given in cm^-1. The name of this file must be written in the Input file, under the FREQ keyword. Note that the first column of the frequencies file must contains the degeneracy of each vibrational mode (an integer number in the interval 1-3)

  4. An input.txt file containing instructions and parameters for the execution of the program.

Optional files:

  1. A file containing data for the LO-TO splitting: it is required to activate a correction for the LO-TO splitting. The name of the such file must be provided under the keyword LO in the Input file. Such LO file must contains two columns: the first one contains the progressive number of the modes affected by LO-TO splitting (the numbering follows the same order of the modes found in the frequencies file); the second column contains the corresponding split values (in cm^-1)

  2. A file containing experimental data of specific heat and entropy, to be used for comparisons with computed results (by the function compare_exp). The name of this file must be written in the Input file, under the EXP keyword

  3. Files for the phonon dispersion correction (see the tutorial)

  4. Files for the anharmonic correction (see the tutorial)

  5. A quick_start.txt file in the master folder. This file contains the name of the folder of the data to be processed. If this file exists, the program immediately proceeds to read the relevant data files, without having to issue the read_file and the static commands

  6. A static pressures file. The file must contain a list of unit cell volumes (in A^3) and the corrisponding static pressures (in GPa). The name of this file must be written in the Input file under the PSTATIC keyword. Note that, with this keyword, the name of the file must be followed by the static energy value at the equilibrium unit cell volume.

Note:

A special parame.py mandatory file must be always present in the master folder. It contains several parameters for the execution of some functions of the program, which could possibly be modified by expert users and developers only.