Accession Number:

AD0672849

Title:

FLUORESCENCE AND PHOSPHORESCENCE OF AROMATIC HYDROCARBONS IN POLY(METHYLMETHACRYLATE) AS A FUNCTION OF TEMPERATURE,

Descriptive Note:

Corporate Author:

TRW SYSTEMS REDONDO BEACH CALIF CHEMICAL SCIENCES DEPT

Personal Author(s):

• Kropp,John L.
• Dawson,William R.

Report Date:

1968-01-01

Pagination or Media Count:

16.0

Abstract:

Fluorescence lifetimes t and fluorescence yieldsP of polymethylmethacrylate samples containing coronene-h12, coronene-d12, pyrene-h10, pyrene-d10, 1,25,6 dibenzanthracene, 1,27,8 dibenzanthracene, 1,23,4 dibenzanthracene, 1,2 benzcoronene and 1,12 benzperylene were measured. For all compounds studied, except coronene-h12 and coronene-d12, t decreases with increasing temperature. For all compounds except 1,12 benzperylene and 1,23,4 dibenzanthracene, P decreases proportionally with t so that the radiative lifetime t is temperature independent. For the two last mentioned compounds t varies with temperature. This may be due to the closeness of the p band to the lowest-lying alpha band. The activation energies of temperature dependent quenching of t are all similar. The quenching is related to Lins theory of radiationless transitions and it is suggested that this temperature dependent quenching is due to S1 -- So transitions. Author

Descriptors:

• (*AROMATIC COMPOUNDS
• *FLUORESCENCE)
• (*POLYCYCLIC COMPOUNDS
• *PHOSPHORESCENCE)
• PRESSURE
• EXCITATION
• RELAXATION TIME
• ANTHRACENES
• BAND SPECTRA
• QUENCHING(INHIBITION)
• SOLID SOLUTIONS
• ACRYLIC RESINS

Subject Categories:

• Radiation and Nuclear Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE