Guest Solvent‐dependence of the Nanomechanical Response in Substituted Dihydropyrimidinone Crystals

The nanomechanical responses of two crystalline phases of a dihydropyrimidine analogue (1) were similar irrespective of the presence (or absence) of the guest solvent. In contrast, the mechanical responses of two differently solvated forms of the second related (2) crystals were significantly different. These contrasting behaviors are rationalized in terms of intermolecular interactions and energy distributions. Guests come and go: Nanomechanical properties (hardness and elastic modulus) of molecular crystals alter depending upon the absence and presence of different guest solvent molecules for two dihydropyrimidine equivalents. A molecular basis in terms of intermolecular interaction patterns and energy distributions justifies the modulation of nanomechanical responses.