Two novel hyperbranched poly (aryl ether)s with azobenzene moieties in both the main chain and side chain of the branched arms were prepared by using B 3 + A 2 methodology via a nucleophilic aromatic substitution polycondensation. Structures of the hyperbranched poly (aryl ether)s with azobenzene moieties (azo-HPAEs) were characterized by means of IR, UV-visible, 1 H NMR spectroscopy, and XRD. It is shown that both the azo-HPAEs exhibit high glass transition temperatures (T g ), excellent thermal stability and homogeneous photochromic behavior. By exposing their spin-coating films to an interference pattern of laser beam, both the azo-HPAEs could be used for rapid (within 30 s) fabrication of surface-relief gratings (SRGs). The obtained SRGs present no shape changes even at temperatures up to 200 C. Especially, the azo-HPAE with azobenzene moieties in the side chain shows larger photoinduced birefringence intensity and better reversible optical storage than the one with azobenzene moieties in the main chain upon irradiation with 532 nm Nd:YAG laser. The novel azo-PAEs are photoactive to UV light (355 nm), making them potentially useful for high density information storage.

Chitosan Azo derivatives show characteristic birefringence property.

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Radiative lifetimes for 14 odd-parity levels with the energy range between 31,654.79 and 47; 184.52 cm −1 of Mo I have been measured using the time-resolved laser-induced fluorescence technique. The lifetime values range from 7.7 to 53.6 ns. Branching fraction measurements of these levels were performed based on the emission spectrum of a hollow cathode lamp. By combining the measured lifetimes and branching fractions, absolute transition probabilities and oscillator strengths for 130 transitions in the wavelength range extending from 275.430 to 600.478 nm have been derived.