Fix 1/2 factor in energy

examples/mliap/jax/mliap_unified_jax.py

@@ -15,8 +15,8 @@ def lj_potential(epsilon, sigma, rij):
         lj1 = 4.0 * epsilon * sigma**12
         lj2 = 4.0 * epsilon * sigma**6
 
-        eij = 0.5 * r6inv * (lj1 * r6inv - lj2)
-        return jnp.sum(eij), eij
+        eij = r6inv * (lj1 * r6inv - lj2)
+        return 0.5 * jnp.sum(eij), eij
     # Construct a function computing _tot_e and its derivative
     (_, eij), fij = jax.value_and_grad(_tot_e, has_aux=True)(rij)
     return eij, fij