In the γ-valerolactone case study, the setup of the most favourable fragment library is 585 identified through a parameter study. The study indicates that a fragment library with acti-vated parameters W F (weighting of the fragments) and S F (substitution of hydrogen atoms) positively impacts the performance of molecular design. With this parameter combination, the effect of the parameter N F in (the number of top-ranked screened candidate molecules used as input in the Fragmentation phase) is negligible.