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

Abstract

AbstractN‐(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 (P21/c), polycrystalline thin films of 1 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 © 2007 John Wiley & Sons, Ltd.