Using the top 1,000 donors and acceptors, a GA found good combinations to optimize absorption with target D/A subcells for tandem OSCs. A strategy observed to improve the spectral range absorbance is to use different classes of NFAs in the two subcells, such as a Y-series acceptor in the front cell and an unfused accep-tor in the rear cell. Not only was this GA strategy successful at finding materials with strong absorbance, but the combinations are predicted to have high PCEs. Utilization of GAs is a great approach to solving complex optimization problems and uncovering structure-property relationships.