Study of a new crowned azobenzene: Photochromism and Langmuir-Blodgett film

A new crowned azobenzene derivative, 4-[(aza-15-crown-5)-13-yl]-4'-methoxya zobenzene (APCM), was synthesized and incorporated into ap cyclodextrin der ivative, heptakis(6-undecylaminoa-6-deoxy)-beta-cyclodextrin (ACD). The cro wned azobenzene showed a large red shift of the maximum UV-vis absorption w avelength upon 254 or 365 nm irradiation. The results from UV-vis and ESR s pectral analyses revealed that the photochromic mechanism for the crowned a zobenzene was a photoinduced intramolecular charge-transfer (CT) process. A PCM/ACD formed a stable Langmuir monolayer at the air-water interface. A mu ltilayer Langmuir-Blodgett (LB) film was constructed from APCM/ACD monolaye rs, which showed a nonlinear polarisability (beta) of 4x10(-29) esu after o ne month of storage.