Atomic Simulation Environment

ASE calculator implementation for the xtb program.

This module provides the basic single point calculator implementation to integrate the xtb API into existing ASE workflows.

Supported properties by this calculator are:

  • energy (free_energy)
  • forces
  • stress (GFN0-xTB only)
  • dipole
  • charges


>>> from import molecule
>>> from xtb.ase.calculator import XTB
>>> atoms = molecule('H2O')
>>> atoms.calc = XTB(method="GFN2-xTB")
>>> atoms.get_potential_energy()
>>> atoms.get_forces()
[[ 1.30837706e-16  1.07043680e-15 -7.49514699e-01]
 [-1.05862195e-16 -1.53501989e-01  3.74757349e-01]
 [-2.49755108e-17  1.53501989e-01  3.74757349e-01]]

Supported keywords are

Keyword Default Description
method “GFN2-xTB” Underlying method for energy and forces
accuracy 1.0 Numerical accuracy of the calculation
electronic_temperature 300.0 Electronic temperatur for TB methods
max_iterations 250 Iterations for self-consistent evaluation
solvent “none” GBSA implicit solvent model
cache_api True Reuse generate API objects (recommended)