morse_pair

torch_sim.models.morse.morse_pair(dr, zi, zj, sigma=1.0, epsilon=5.0, alpha=5.0)[source]

Morse pair energy.

V(r) = ε(1 - exp(-α(r - σ)))² - ε

Parameters:
  • dr (Tensor) – Pairwise distances, shape [n_pairs].

  • zi (Tensor) – Atomic numbers of first atoms (unused).

  • zj (Tensor) – Atomic numbers of second atoms (unused).

  • sigma (Tensor | float) – Equilibrium bond distance. Defaults to 1.0.

  • epsilon (Tensor | float) – Well depth / dissociation energy. Defaults to 5.0.

  • alpha (Tensor | float) – Width parameter. Defaults to 5.0.

Returns:

Pair energies, shape [n_pairs].

Return type:

Tensor