From detailed optically detected magnetic resonance measurements in polythiophene, we show that the g=2.003 signal is luminescence enhancing, and that the signal comes from a broad photoluminescence band peaking near 1.65 eV. This band is tentatively assigned to Phe radiative recombination of polarons, with lifetimes between 10-8 and 5×10-5sec.

Efficient, phase-matched second-harmonic generation of 1.064 µm radiation has been observed with single crystals of 4-aminobenzophenone (ABP). These crystals are tr nsparent from 420–2000 nm and have damage thresholds exceeding 30 GW/cm2 (for a 30-picosecond laser pulse).

We propose a new method for the determination of the electro-optic constant. Third-order nonlinear susceptibility (X(3)(-ω;ω,0, 0)) of polycarbonate films doped with 4-diethylamino-4′-nitrostilbene molecules was determined between 550 and 800 nm at room temperature by using this method. X(3)(-ω;ω0, 0) is (5-4i) × 10-12 esu at 600 nm.

Highly oriented, unsubstituted polydiacetylene was obtained by the polymerization of 1,3-butadiyne in perhydrotriphenylene (PHTP). The canal structure of PHTP induces a high degree of order in the polymer. Transparent orange crystals were formed which were shown by SEM to consist of structures oriented parallel to the long axis of the crystal. Resonance Raman and UV-visible spectroscopy indicate the polymer consists of seven to ten conjugated ene-yne type repeat units. Crystallization of the inclusion complex was induced inside glass capillaries so the crystals filled the entire space along the length of the capillary.