DETERMINATION OF THE MEAN LIFE OF THE FIRST EXCITED STATE OF SOME COMPLEX AROMATIC COMPOUNDS IN AERATED SOLUTION AND THE ABSOLUTE QUANTUM YIELD OF FLUORESCENCE OF BIACETYL IN SOLUTION,
Abstract
The transfer of electronic excitation energy from the lowest excited singlet state of naphtha lene, benzene and twelve of its alkyl deriva tives to the lowest excited singlet state of biacetyl was studied in aerated hexane solu tions at 28 degrees by the spectrophotofluoro metric method. Stern-Volmer diagrams were drawn to show the donor quenching by the acceptor under conditions of low optical density. Slopes obtained from these curves are independent of donor concentration and equal to K times tau, where k is the specific rate constant for the transfer process and tau is the lifetime of the donor's singlet state in aerated solutions. A value for tau is obtained if it is assumed that the collisional transfer efficiency is unity and that the specific rate constant can be calcu lated by use of the Debye equation. Lifetimes obtained in this manner agree with those measured directly by Ivanova for the same donors after the latter's work has been corrected for self quenching. The absolute quantum yield of fluo rescence of anthracene in ethanol was calculated by a comparison of its fluorescence spectrum with that of the quinine bisulfate standard; the experimental result agrees with the published literature values. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1963
- Accession Number
- AD0418562
Entities
People
- Rudy Lee Van
Organizations
- Air Force Institute of Technology