1. Estimating all physical properties in the training dataset by simulation and their gradients with respect to the LJ parameters being optimized, using the OpenFF Evaluator software package. 2. Calculating the value of the objective function at the current parameter set. This optimization is allowed to continue until the objective function is observed to fluctuate around a constant minimum. The minor fluctuations around the minimum in the objective function are expected due to noise in the gradients of the physical properties with respect to the LJ parameters caused by finite simulation lengths. In practice it was found that 15 iterations was sufficient to consistently meet this criteria, which was completed in roughly one week requesting resources from a pool of 60 GPUs.