Supramolecular steric hindrance effect on morphologies and photophysical behaviors of spirocyclic aromatic hydrocarbon nanocrystals.

Three pyrene-based spirocyclic aromatic hydrocarbons (Py-SAHs) were prepared to clarify the roles of molecular segments in regulating the morphologies and photophysical properties of organic microcrystals. Due to the different supramolecular steric hindrance (SSH) effect between bulky groups and pyrene rings, distinct nanocrystal morphologies with unique photoluminescence properties were realized.