Training data only from the Co_dimer_JPCA_2022 dataset. This dataset contains dimer molecules of Co(II) with potential energy calculations for structures with ferromagnetic and antiferromagnetic spin configurations. Calculations were carried out in Gaussian 16 with the PBE exchange-correlation functional and 6-31+G* basis set. All molecules contain the same atomic core region, consisting of the tetrahedral and octahedral Co centers and the three PO2R2 bridging ligands. The ligand exchange provides a broad range of exchange energies (ΔEJ), from +50 to -200 meV, with 80% of the ligands yielding ΔEJ < 10 meV.