Influence of temperature on rare earth sandwich double naphthalocyanines Langmuir-Blodgett multilayer films

Using linear absorption spectra and second harmonic generation(SHG) technique, the influence of temperature on optical properties and Langmuir-Blodgett(LB) films structure of rare earth sandwich double naphthalocyanines were investigated.The absorption spectra show that the LB film structure and interaction between the molecules have been changed by heating. The bi-(tetra-tert-butyl-naphthalocyaninato)-orbium molecules formed J-aggregates in LB films, which resulted in absorption spectra red shift. A maximum of the second harmonic generation signal intensity was observed at about 65 ℃ due to a first-order phase transition. The minimum of the second harmonic generation signal intensity was obtained at about 180 ℃, which means that the molecule structure is stable.