Another type where splitting may yield improved results is the [#6:1] generic carbon type. In the training set; this type is only exercised by carbonyls, but in the test set this type is exercised by both carbonyls and alkenes. While the changes introduced in the multi-fidelity optimization significant improve performance of carbonyl-containing molecules, binary densities of alkene mixtures are significantly degraded, indicating that the type may no longer be suitable for describing both contexts. This is sensible as carbonyls and alkenes are quite different in their chemistry.