lennard_jones_pair_force

torch_sim.models.lennard_jones.lennard_jones_pair_force(dr, sigma=1.0, epsilon=1.0)

Lennard-Jones 12-6 pair force (negative gradient of energy).

F(r) = 24ε/r [2(σ/r)¹² - (σ/r)⁶]

Parameters:

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

• sigma (Tensor | float) – Length scale. Defaults to 1.0.

• epsilon (Tensor | float) – Energy scale. Defaults to 1.0.

Returns:

Pair force magnitudes (positive = repulsive), shape [n_pairs].

Return type:

Tensor