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Program: CALANIE

        CALculation of ANIsotropic Elastic interaction energy of
        a defect in periodic boundary conditions

Version: 2.0

Date: 06 Dec 2018

Author: Pui-Wai (Leo) MA

Contact: [email protected]

Address: Culham Centre for Fusion Energy, OX14 3DB, United Kingdom

This program calculate the elastic interaction energy of a defect with its images in periodc boundary conditions. It also output the elastic dipole tensor and relaxation volume tensor.

It requires two input files: input_data & input_elastic. "input_data" will be discussed here.

"input_elastic" contains the information of elastic constant tensor. Format of it is mentioned in "make_input_elastic.py".

One can compile the program in 2 ways.

1. g++ -DORIENTATION CALANIE_version.cpp

   This requires input of

   (1) Reference simulation box vectors

   (2) Lattice unit for reference box vectors

   (3) Relaxation volumes Omega1 and Omega2

   (4) Orientation of the defect

   Put (1) to (3) in a file with name "input_data", and also the "input_elastic".

   Run the program by

   ./a.out theta phi

   where theta and phi are (4) Orientation of the defect

   Detail is in S. L. Dudarev and Pui-Wai Ma, Physical Review Materials 2 (3), 033602 (2018)

Or

2. g++ -DABINITIO -DSTRESSeV CALANIE_version.cpp

   or

   g++ -DABINITIO -DSTRESSGPa CALANIE_version.cpp

   This require input of

   (1) Reference simulation box vectors

   (2) Lattice units for reference simulation box vectors

   (3) Total marcoscopic stress of the reference simulation box (in eV or GPa)

   (4) Defect simulation box vectors

   (5) Lattice units for defect simulation box vectors

   (6) Total marcoscopic stress of the defect simulation box (in eV or GPa)

   Put (1) to (6) in a file with name "input_data"

   Run the program by

   ./a.out

   Detail is in Pui-Wai Ma and S. L. Dudarev, Physical Review Materials, 3 (1), 013605, (2019)

   Note:

   -DSTRESSeV means total stresses multiply volume. Unit is in eV. It is exactly the line of "Total" in vasp "OUTCAR".

   -DSTRESSGPa means total stresses. Unit is in GPa. It is corresponding to the line of "kB" in vasp "OUTCAR", where "kB" means kbar = 0.1GPa.

A sperhical summation up to a radius equals to 10th neighbour cell is used for calculating the E_DD and E_DD_corr terms.

Please read "Note on elastic corrections".

A sample "input_data" is given for both cases. "input_data_1" is for 1st case. "input_data_2" is for 2nd case using -DSTRESSeV.

Sign convention of total marcoscopic stress follow VASP. i.e positive means the simulation cell intends to expand.