Molecular Design of Pyrene and Its Derivatives to Make Microcrystalline Films with Silver Luster Effect Using Drop-Casting Method

We report a new class of metal-free dyes, based on pyrene and its derivatives having tert-butyl groups that show silver luster. This luster film was easily fabricated on a glass substrate by drop-casting an n-hexane solution of the compound. The film was formed by the stacking of very thin, flat, and small platelet-shaped crystals. By varying the number of tert-butyl groups in the pyrene molecule, we were able to control the intermolecular interactions in the crystal and to obtain the optimal crystal for fabricating this film. The silvery textured film was achieved on the pyrene by a combination of characteristic absorption (i.e., no absorption in the visible region) and specular reflection from the surface of the stacked microcrystals.