Axilrod-Teller-Muto (ATM) dispersion term

Axilrod-Teller-Muto (ATM) dispersion term#

This module provides the dispersion energy evaluation for the three-body Axilrod-Teller-Muto dispersion term.

\[\begin{split}E_\text{disp}^{(3), \text{ATM}} &= \sum_\text{ABC} E^{\text{ABC}} f_\text{damp}\left(\overline{R}_\text{ABC}\right) \\ E^{\text{ABC}} &= \dfrac{C^{\text{ABC}}_9 \left(3 \cos\theta_\text{A} \cos\theta_\text{B} \cos\theta_\text{C} + 1 \right)} {\left(r_\text{AB} r_\text{BC} r_\text{AC} \right)^3} \\ f_\text{damp} &= \dfrac{1}{1+ 6 \left(\overline{R}_\text{ABC}\right)^{-16}}\end{split}\]
tad_dftd3.damping.atm.dispersion_atm(numbers, positions, c6, rvdw, cutoff, s9=tensor(1.), rs9=tensor(1.3333), alp=tensor(14.))[source]#

Axilrod-Teller-Muto dispersion term.

  • numbers (Tensor) – Atomic numbers of the atoms in the system.

  • positions (Tensor) – Cartesian coordinates of the atoms in the system.

  • c6 (Tensor) – Atomic C6 dispersion coefficients.

  • rvdw (Tensor) – Van der Waals radii of the atoms in the system.

  • cutoff (Tensor) – Real-space cutoff.

  • s9 (Tensor, optional) – Scaling for dispersion coefficients. Defaults to 1.0.

  • rs9 (Tensor, optional) – Scaling for van-der-Waals radii in damping function. Defaults to 4.0/3.0.

  • alp (Tensor, optional) – Exponent of zero damping function. Defaults to 14.0.


Atom-resolved ATM dispersion energy.

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