where, E X/gr is the total energy of the optimized graphene systems with the x species (H or CH X ) adsorbed, E gr is the energy of pristine graphene, and E X is the energy of the isolated X species. For H atom, the E X is the energy of single atom H from DFT with spin-polarized calculations. Our results for CH X adsorptions show that, except for the case of CH, where the geometry predicted by the ANN potential is not consistent with DFT, the ANN potential effectively captures the relative adsorption strength of CH X species despite differences in E ads between DFT and the ANN potential. Both methods indicate an increase in E ads as the number of H atoms in CH X decreases which is in agreement with other DFT studies.