Polarized light spectroscopy of azobenzene or disperse red 1 with Mn12 single-molecule magnets in PMMA film hybrid materials

Abstract

A series of organic/inorganic hybrid materials containing the single-molecule magnet [Mn12(CH3COO)16 (H2O)4O12]·2CH3 COOH·4H2O with the photochromic compounds azobenzene or disperse red 1 cast into polymethyl methacrylate films was prepared. To understand the photomodulation of analogous mixtures' AC susceptibility, we investigated the molecular alignment based on Weigert's effect accompanying cycles of cis-trans photoisomerization by alternate irradiations with polarized UV and visible light. Polarized electronic spectra of the hybrid materials demonstrated gradually increasing anisotropy. These features suggest interactions between photochromic compounds and the Mn12 complex in polymethyl methacrylate. © Versita Warsaw and Springer-Verlag Berlin Heidelberg 2009.