Investigation of the triplet states of DNA by optical detection of magnetic resonance using a new slow passage technique

✍ Scribed by K.P. Dinse; A.H. Maki

• Publisher: Elsevier Science
• Year: 1976
• Tongue: English
• Weight: 450 KB
• Volume: 38
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(76)80271-0

✦ Synopsis

A now method to obtain slow ~XSZXJC ODMR signals under othcrwisc impcdinz conditions is clcscribcd. 't'hc tcchnipuc is applied to identify the triplet state of DNA as thymino. 'The zero fictd splitting constants measured are I DI = (0.203 i 0.003) an-1 , and I El 7 (0.0123 t 0.0005) cm-l. From micrownvc-induced delayed phosphorescence and slow pas5agc measurcmcnts a preliminary kinetic schcrnc for the triplet state is dcrivcd. * On Icavc from Institut fiir hlolekiilphysik, Frcic Universitiit I~crlin, Germany. ** Eq. (I) is valid when spin.-l;itlicc relaxation is neglected, and under the assumption of mgfigibie change of the gmud-state poprdation whiIe applying the microwave fiejd. The frequently quoted equation A/ 0: (Ni-N,)X (kj-# is not applicable for Ihe discussion of true stendy state slow passage sip& bcc..une its validity requires a conscanf totai triplet population with and without saturating microwave power.