where ∆E 2 and |∆F i | 2 denote the mean squared errors of the total energies and atomic forces. We set initial values of 0.02 and 1,000 to the prefactors p ϵ and p f , respectively. We allowed these parameters to automatically adjust throughout training. Automatic adjustment was used for empirical reasons because the force term dominated at the beginning of the training, whereas the energy term dominated at the end . A cutoff radius of 6 Å with a smoothing of 2 Å was used to train our DPs. Each DP was trained for one million epochs.