Interfaces to calculators

Currently the built-in interfaces for VASP, QUANTUM ESPRESSO (QE), CRYSTAL, Abinit, and TURBOMOLE are prepared. VASP is the default interface and no special option is necessary to invoke it, but for the other interfaces, each special option has to be specified, e.g. --qe, --crystal, --abinit, or --turbomole

Calculator specific behaviors

Physical unit

The interfaces for VASP, QE (pw), CRYSTAL, Abinit, and TURBOMOLE are built in to the phono3py command.

For each calculator, each physical unit system is used. The physical unit systems used for the calculators are summarized below.

          | unit-cell  FORCES_FC3   disp_fc3.yaml
VASP      | Angstrom   eV/Angstrom  Angstrom
QE (pw)   | au (bohr)  Ry/au        au
CRYSTAL   | Angstrom   eV/Angstrom  Angstrom
Abinit    | au (bohr)  eV/Angstrom  au
TURBOMOLE | au (bohr)  hartree/au   au

FORCES_FC2 and disp_fc2.yaml have the same physical units as FORCES_FC3 and disp_fc3.yaml, respectively.

Always (irrespective of calculator interface) the physical units of 2nd and 3rd order force constants that are to be stored in fc2.hdf5 and fc3.hdf5 are \(\text{eV}/\text{Angstrom}^2\) and \(\text{eV}/\text{Angstrom}^3\), respectively.

Default unit cell file name

Default unit cell file names are also changed according to the calculators:

QE        |
CRYSTAL   | crystal.o
Abinit    |
TURBOMOLE | control

Default displacement distance created

Default displacement distances created by -d option without --amplitude option are respectively as follows:

VASP      | 0.03 Angstrom
QE        | 0.06 au (bohr)
CRYSTAL   | 0.03 Angstrom
Abinit    | 0.06 au (bohr)
TURBOMOLE | 0.06 au (bohr)