In situ growth in a PMMA film of oriented nanocrystals of the hybrid inorganic-organic acentric material [(E)-N,N-dimethylamino-N'-methylstilbazolium][Cu5I6]

A poly(methyl methacrylate) (PMMA) composite film containing 4 wt% of the strongly second order NLO active ionic material [(E)-N,N-dimethylamino-N′- methylstilbazonium][Cu5I6] (1), obtained by spin coating of a CH3CN solution on a glass substrate, shows by a two step process (electric poling followed by controlled thermal annealing up to 140°C) in situ growth of nanocrystals, some of which are aligned, with a size of less than 400 nm as supported by TEM and GIXRD evidence. A long lasting second harmonic generation (SHG) is produced which is stable even after exposure to water vapour for one night.