Spin-dependent exciton formation rates in p-conjugated oligomers and polymers
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چکیده
We have measured the ratio, r 1⁄4 sS=sT of the formation cross section, of singlet (S) and triplet (T) excitons from polarons in p-conjugated oligomer and polymer films, using a spectroscopic/magnetic resonance technique. We show that exciton formation from separated polaron pairs in p-conjugated compounds is spin-dependent, specifically r > 1: Moreover, we discovered a universal relation between r and the conjugation length (CL): namely r aðCLÞ : r 2003 Elsevier B.V. All rights reserved. PACS: 78.55.Kz; 72.20.Jv; 78.66.Qn
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تاریخ انتشار 2003