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.