And, OpenFF's default level of theory, B3LYP-D3(BJ)/DZVP, has an RMSE error 0.18 kcal/mol worse than the best method, with an overall RMSE of 0.58 kcal/mol. The difference in RMSE between charged molecules and the neutral molecules is slightly higher for B3LYP-D3(BJ)/DZVP level of theory, and addition of basis functions helped drive this error down.