Force prediction in the Gaussian process model

[zyt0y]

Hi all,

I have noticed that CatLearn includes both energy and forces in the training of a Gaussian process model, but only predicts energy from the GP model. The predicted forces are computed using finite differences according to Phys. Rev. Lett. 122, 156001 (2019) . However, predicting forces directly from the GP model is also starightforward once forces are included in the training just as what J. Chem. Phys. 147, 152720 (2017) did. Why not predicting forces directly from the GP model in CatLearn? Is there any benifit of using the finite difference approach?

Best,
Zeyuan