Accession Number : AD0646739

Title :   EFFECTS OF HIGH PRESSURES ON THE PHOSPHORESCENCE OF AROMATIC HYDROCARBONS.

Descriptive Note : Technical rept.,

Corporate Author : CALIFORNIA UNIV SANTA BARBARA DEPT OF CHEMISTRY

Personal Author(s) : Baldwin,B. A. ; Offen,H. W.

Report Date : 23 JAN 1967

Pagination or Media Count : 30

Abstract : The phosphorescence spectra, intensities and lifetimes were measured for ten aromatic hydrocarbons, dispersed in polymethylmethacrylate, in the 0-32 kbar pressure range at 298K. It was observed that the red shift is small (200-450/cm at 32 kbar) and comparable to the red shift observed in fluorescence. The measured phosphorescence lifetime decreases montonically with increasing pressures over the 0-32 kbar range for nine of the ten aromatics. From dynamic intensity measurements at 0, 10, and 20 kbar pressure it is concluded that the natural lifetime decreases by about 30% at 20 kbar. Also, the radiationless rate constant must increase by roughly the same amount. It is concluded that pressure enhances spin-orbit interaction and the vibrational overlap factors. (Author)

Descriptors :   (*HYDROCARBONS, *PHOSPHORESCENCE), AROMATIC COMPOUNDS, HIGH PRESSURE, SPECTROSCOPY

Subject Categories : Organic Chemistry
      Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE