Sol–Gel Preparation and Optical Nonlinearity of Lead(ll) Oxide–Titanium(IV) Oxide Amorphous Monoliths

PbO–TiO2 amorphous monoliths with TiO 2 content from 60 to 80 mol% were prepared by fbc sol–gel method using Pb–Ti complex alkoxides synthesized from Pb(CH 3 ,COO) 2 ·3H 2 O and Ti(O·C 3 H 7 ia ) 4 . The thermal evolution process of the gel was examined by means of DTA/TG, IR spectros–copy, and X–ray diffraction techniques. Dehydrated, transparent, amorphous monoliths were obtained in the temperature range from 350° to 550°C, depending on the composition. The refractive index of those amorphous monoliths was higher than 2.0, and the third–order optical nonlinear susceptibility, X (3) , evaluated from third harmonic generation (THG) was on the order of 10 ‐12 esu.