A simple fortran program to set the input (case.ing file) of GIBBS2 code (https://aoterodelaroza.github.io/gibbs2/ )

to compile the program:

 gfortran set_input_gibbs2.f90  -o  set_input_gibbs2

or:

 ifort  set_input_gibbs2.f90  -o  set_input_gibbs2

to execute:

./set_input_gibbs2

Example: input data for Gibbs2
https://aoterodelaroza.github.io/gibbs2/

     Necessary  input paramaters obtained from your ab initio code 
     The bulmk modulus        : B    (GPa)                         
     The prussure derivative  : Bp                            
     The volume               : V0   ( a.u^3)                         
     The total energy at V0   : E0   (Ry  )                       
     MM, the molecularmass of the primitive cell (in a.m.u )      
     VFREE,the total number of atoms in the primitive cell.   
      ********************* 07/01/2024 pg@G.Benabdellah *****************
        ---> Enter the volume (in  a.u^3)  : V0=   200
       ---> Enter the bulmk modulus (in GPa ) : B=  120
       ---> Enter the prussure derivative of B: Bp= 4.5
       ---> Enter the equilibrium total energy at V0 ( in Ry) : E0= -3500.  
       
       for  Equation of state: Murnaghan       enter:  m  
       for  Equation of state: Birch-Murnaghan enter:  mb 
       
       ---> Enter your choose (  m | mb) :  m
       
        ---| Equilibrium volume V0 =    200.     
        ---> Eneter the Number of fitted points:(default n=100) : n = 100
       ---> Enter the total number of atoms in the primitive cell: VFREE = 4
       ---> Enter :The molecular Masse of the primitive cell in a.m.u: mm = 98.2
       ---> Enter the phase name (free format) : phase_name =  XXXX
                 
       ---> Enter the pressure range: P_init; P_step ;P_final :
        --> pressure range: P_init = 0 
        --> pressure range: P_step = 1
        --> pressure range: P_final = 20
      ---> Enter the temperature range: T_init; T_step ; T_final :
        --> temperature range: T_init = 50
        --> temperature range: T_step = 50
        --> temperature range: T_final= 500

The units of Gibbs2 : volumes (in bohr^3 ) and energies (in Hartree ).

out data in file: case.ing

  mm   98.2000
  vfree  4
  pressure      0.00      1.00     20.00
  temperature     50.00     50.00    500.00
  phase XXXX          fit        murn 
    170.000004768372       -1749.98750289720     
    170.600004673004       -1749.98808042011     
    171.200004577637       -1749.98864033153     
    171.800004482269       -1749.98918296826     
    172.400004386902       -1749.98970865954     
    173.000004291534       -1749.99021772720     
    173.600004196167       -1749.99071048587     
    174.200004100800       -1749.99118724319     
    ...
    ....
   endphase