Rational (Becke-Johnson) damping function

Rational (Becke-Johnson) damping function#

This module defines the rational damping function, also known as Becke-Johnson damping.

\[f^n_{\text{damp}}\left(R_0^{\text{AB}}\right) = \dfrac{R^n_{\text{AB}}}{R^n_{\text{AB}} + \left( a_1 R_0^{\text{AB}} + a_2 \right)^n}\]
tad_dftd3.damping.rational.rational_damping(order, distances, qq, param)[source]#

Rational damped dispersion interaction between pairs.

Parameters:
  • order (int) – Order of the dispersion interaction, e.g. 6 for dipole-dipole, 8 for dipole-quadrupole and so on.

  • distances (Tensor) – Pairwise distances between atoms in the system.

  • qq (Tensor) – Quotient of C8 and C6 dispersion coefficients.

  • param (dict[str, Tensor]) – DFT-D3 damping parameters.

Returns:

Values of the damping function.

Return type:

Tensor