| In a photoresponsive Langmuir monolayer comprised of Smectic-C-like domains of mesogenic trans-azobenzene derivative embedded within an isotropic matrix of its cis isomer counterpart, several different phenomena of photoinduced molecular reorientation patterns will be reported. Observations, based on Brewster Angle Microscopy analysis, permit to identify both photoalignment process, with molecules aiming to orient themselves perpendicular to the polarized illumination, and, additionally, nucleation and propagation of localized orientational waves. The dynamical aspects of both scenarios are captured by a theoretical model based on a free-energy formulation that couples a relaxational principle, incorporating long range elastic forces, with a kinetic formalism using an anisotropic rate law. - J. Ignés-Mulllol et al., Langmuir 21, 2948-2955 (2005) - F. Sagués et al., JACS 127, 5296-5297 (2005) - P. Burriel et al., Langmuir 22, 187 (2006) - J. Claret et al., Phys. Rev. E 73, 026225 (2006) - J. Claret et al., Eur. Phys. J. E 21, 111 (2006) |
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