Skip to main content
`Ctrl`+`K`

# DMol3

DMol3 is an atomic orbital DFT code.

## Environment variables

DMOL_COMMAND should point to the RunDmol script

    $ export DMOL_COMMAND="./RunDmol.sh -np 16"

## DMol3 Calculator

The DMol3 calculator is a FileIOCalculator. The default setting used by the dmol interface is

class ase.calculators.dmol.DMol3(functional='pbe', symmetry='on')

The dmol calculator supports the calculate gradient function in DMol3, meaning the internal relaxation is not supported. Forces and potential energy are the supported properties

    implemented_properties = ['energy', 'forces']

Note

DMol3 often reorients the atomic system. Therefore it’s recommended to use the calculator with care. Forces are reoriented to match the atoms object, however properties like k-points and density files (.grd) may be misoriented when reading.

Note

Only 3D periodic systems (pbc = [True, True, True]) and fully non-periodic systems are supported by the DMol3 calculator.

## Example

    from ase.build import molecule
    from ase.calculators.dmol import DMol3

    atoms = molecule('H2O')
    calc = DMol3(symmetry='auto',
                 spin_polarization='unrestricted',
                 charge=0,
                 basis='dnp',
                 pseudopotential='none',
                 functional='pbe',
                 scf_density_convergence=1.0e-7)
    atoms.calc = calc
    atoms.get_potential_energy()

## File formats

The supported dmol file formats (for write/read) are

- .car

- .incoor

- .arc

For molecules and systems without periodic boundary conditions, the .car format is used, while for periodic systems the .incoor format, which allows specification of the unit cell, is used. The .arc files are trajectory files from internal relaxation runs in DMol3 (which is not supported by this calculator)