“…The metrics of training sample , validation sample , and test sample are 0.964, 0.918, 0.907 for H element, 0.975, 0.931, 0.931 for C element, 0.950, 0.889, 0.865 for N element, and, 0.935, 0.867, 0.902 for O element. All these results satisfy the fitting criterion (note that indicates overfitting), 22 indicating that the NNs for H, C, N, and O elements (i.e., the HDNN model) are reliable for p atom ( σ ) predictions. However, it should be noted that for the N element‐based NN model, the fitting criterion is , which is close to the upper bound (0.1).…”