Sequential Self-Organization of Silver(I) Layered Materials with Strong SHG by J Aggregation and Intercalation of Organic Nonlinear Optical Chromophores through Mechanochemical Synthesis

The inorganic-organic hybrid layered material of stoichiometry [DAMS+][Ag5I6-], characterized by a strong SHG activity, has been prepared mechanochemically by room-temperature ball-milling a mixture of AgI and [DAMS+][I-], eventually followed by a moderate heating. By means of electronic absorption spectra, XRPD, and second harmonic generation (SHG) experiments we proved that the intralayer ordering of the [DAMS+] nonlinear optical chromophores into J-aggregates precedes the interlayer one, on the whole producing, by a sequential process, the "macropolarity" responsible for the strong SHG. The mechanochemical approach was shown to be of general use, as it was successfully applied to the synthesis of the analogous [DAMS+][Cu5I6-], [DAZOP+][Ag5I6-], and [DAES+][Ag5I6-] materials.