In this work, DC-DFT and other models will be used to correct intramolecular conformational energies and then the monomer correction approach 26 is employed to examine the impact of the corrected conformational energies on polymorph stabilities. In this approach, one first performs a periodic DFT calculation on the full crystal, and herein that energy (E DFT crystal ) is computed using the B86bPBE+XDM functional, as in previous work. Then, for each of the N molecules in the unit cell, one computes a gas-phase energy difference between the lowlevel DFT treatment that is used for the periodic calculation (E DFT molec,i ) and a more advanced level of theory (E high molec,i ), where the "high-level" method could be DC-DFT or else a correlated wave function method. The crystal energy approximated in this way is