Pressure Dependence of Benzophenone Phosphorescence

Publisher Website
Google Scholar
Abstract
The phosphorescence spectrum, intensity, and lifetime of benzophenone have been studied at 77°K as a function of pressure (0–30 kbar) in EPA, polymethylmethacrylate (PMMA), and polyethylene (PE). At 30 kbar the tiplet energy is raised 90 cm−1 in EPA and lowered about 460 cm−1 in PMMA and PE, according to the pressure‐induced, reversible shift of the band origin. The triplet lifetime in EPA is reduced from 5.8 to 4.5 msec at 30 kbar pressure. A decrease in phosphorescence intensity suggests that the radiative transition probability diminishes under pressure. The intensity decay becomes strongly nonexponential in polymer matrices under compression.