torch_sim.models.morse

Anharmonic interatomic potential for molecular dynamics.

This module implements the Morse potential for molecular dynamics simulations. The Morse potential provides a more realistic description of anharmonic bond behavior than simple harmonic potentials, capturing bond breaking and formation. It includes both energy and force calculations with support for neighbor lists.

Example:

# Create a Morse model with default parameters
model = MorseModel(device=torch.device("cuda"))

# Calculate properties for a simulation state
output = model(sim_state)
energy = output["energy"]
forces = output["forces"]

Notes

The Morse potential follows the form: V(r) = D_e * (1 - exp(-a(r-r_e)))^2

Where: - D_e (epsilon) is the well depth (dissociation energy) - r_e (sigma) is the equilibrium bond distance - a (alpha) controls the width of the potential well

Classes

MorseModel

Morse potential energy and force calculator.