Chromophore aggregation hampers photoisomerization in Langmuir-Blodgett films of stearoyl ester of Disperse Red-13 (DR13St)

Aggregation of azobenzene chromophores in Langmuir-Blodgett films of stearoyl ester of Disperse Red-13 (DR13St) and cadmium stearate (CdSt) hampers the trans-cis photoisomerization that normally leads to optical storage capabilities, since the required free volume around the chromophore is not available. Such aggregation has been inferred by UV-VIS. spectroscopy and X-ray diffraction. Optical storage properties could still be obtained if DR13St was mixed in a guest-host system with a polycarbonate matrix. (C) 2000 Elsevier Science B.V. All rights reserved.