N-(3,5-Di-tert-butylsalicylidene)-4-iodobenzene, a peculiar case of a nonlinear optical photoswitch

摘要

N-(3,5-Di-tert-butylsalicylidene)-4-iodobenzene (1) is photochromic in the solid state, owing to its ability to yield enol-keto tautomerism. Despite its centrosymmetric structure (P2(1)/c), polycrystalline thin films of I show second harmonic generation (SHG). Moreover, this SHG can be reversibly switched by light. Investigations using confocal microscopy showed that a morphology change occurs when the fundamental beam of a Ti:sapphire (990 nm, 1.3 ps) is focused on the material, yielding an SHG-active solid. Copyright (c) 2007 John Wiley & Sons, Ltd.