Spin dynamics of neutral radical pairs in single crystals of di-tert-butyl-pryrocatechol doped with tetrakis(t-butyl)-phenoxazin

✍ Scribed by G.G. Lazarev; V.L. Kuskov; K. Laukenmann; A. Angerhofer

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 688 KB
• Volume: 215
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(93)85732-4

✦ Synopsis

The electron spin relaxation in radical pairs formed by photolysis of single crystals of 3,5-d&tert-butylpyrocatechol, doped with 10s2 M I-H-2,4,6,8-tetrakis( t-butyl)phenoxazine-l-one was studied by pulsed and stationary EPR in X-band in the temperature range 10-90 K. The relaxation patterns were partly biexponential and were interpreted within the frame of the four-level model of the radical pair, demonstrating the importance of the singlet level in the spin relaxation process. Angular dependencies of the characteristic relaxation times T, and T, were measured as well as the temperature dependence of T,. In three cases asymmetric relaxation was found. Excitation spectra of the EPR signals show that different radical pairs (RP) may be distinguished by their action spectra.