nanotools.relax module

Created on 2021-06-04

@author: Vincent Michaud-Rioux

class nanotools.relax.Relax(reference_calculator, fixatoms=None, ftol=0.01, restart: bool = True)[source]

Bases: Base

Relax class.

Examples:

from ase.build import bulk
from nanotools import System, TotalEnergy, Relax

a = 5.43 # lattice constant in ang
atoms = bulk("Si", "diamond", a=a, cubic=True)
# move atoms around a bit
atoms.rattle(stdev=0.05, seed=1)
atoms.positions[0,:] = 0.

sys = System.from_ase_atoms(atoms)
sys.cell.set_resolution(0.2)
sys.kpoint.set_grid([5,5,5])
ecalc = TotalEnergy(sys)
ecalc.solver.mix.alpha = 0.5
ecalc.solver.set_mpi_command("mpiexec --bind-to core -n 16")
rlx = Relax.from_totalenergy(ecalc)
rlx.solve()

fixatoms: Atoms with indices in fixatoms will be kept fixed during the relaxation procedure.

ftol

Force tolerance. The relaxation procedure stop once all forces are less than the tolerance.

Type:: pint.registry.Quantity

reference_calculator

Total energy calculator.

Type:: nanotools.totalenergy.TotalEnergy

restart

Use real space density matrix to restart between iterations.

Type:: bool