To characterize the experimental stability of the 2and 3-fold structures, we subjected solvated crystals to direct activation under vacuum at 100 °C. We also activated the materials by first exchanging the crystallization solvent with n-pentane and then evacuating at room temperature. However, we found that the 2-fold and 3-fold structures transformed to the 5-fold structure after activation under both conditions (SI, Figures ); neither the 2-fold nor 3-fold interpenetrated packing of ADTA have been isolated as solvent-free crystals.