Table 4. Test set RMSEs for 
in kcal per mol per HFX separated by metal and oxidation state along with minimum and maximum unsigned test errors (UE). The number of test cases is indicated in parentheses.
| Species | RMSE | Min. UE | Max. UE |
| Cr(ii) | 21 (14) | 4 | 45 |
| Cr(iii) | 17 (8) | 2 | 37 |
| Mn(ii) | 24 (6) | 3 | 40 |
| Mn(iii) | 38 (8) | 4 | 92 |
| Fe(ii) | 18 (9) | 2 | 41 |
| Fe(iii) | 15 (12) | <1 | 32 |
| Co(ii) | 17 (8) | <1 | 26 |
| Co(iii) | 20 (8) | <1 | 46 |
| Ni(ii) | 9 (4) | 1 | 15 |