ABSTRACT
Silica-coated gold nanorods functionalized with grafted fluorescent and photochromic derivatives were synthesized and characterized. Spectroscopic investigations demonstrated that cross-coupled interactions between plasmonic, photochromic, and fluorescence properties play a major role in such nanosystems, depending on the thickness of the silica spacer, leading to multi-signal photoswitchability.
Subject(s)
Fluorescent Dyes/chemistry , Nanostructures , Microscopy, Electron, ScanningABSTRACT
Microcrystals of a diarylethene {1,2-bis[5'-methyl-2'-(2"-pyridyl)thiazolyl]perfluorocyclo-pentene} undergo jumps upon photoirradiation. These photochromic crystals present molecular structural changes upon irradiation with ultraviolet light because of reversible photocyclization reactions. When the energy absorbed by crystals reaches about 10 microJ, the uniaxial stress induced in the crystal lattice relaxes through directional jumps. If one prevents crystals from jumping, then parallel, equidistant cracks appear on crystal surfaces. These photomechanical effects could result from a Grinfeld surface instability.