Abstract: Energy transfer in fluorescent donor–acceptor pairs is typically governed by one of two mechanisms: Förster Resonance Energy Transfer (FRET) or Through-Bond Energy Transfer (TBET). In contrast to FRET, TBET has been widely assumed to require π-conjugation between the donor and acceptor units. In this work, we introduce a versatile strategy for simulating nonadiabatic quantum dynamics in large molecular systems and apply it to a dye CouXan featuring a coumarin donor, a xanthene acceptor and a non-π-conjugated diazinane linker. We demonstrate that strong vibronic coupling drives highly efficient TBET with a remarkable rate constant of 6.8 × 10^12 s–1 even in the absence of π-conjugation, surpassing the known FRET rate (8.0 × 10^10 s–1) by 2 orders of magnitude. This finding challenges the present understanding of energy transfer in donor–acceptor pairs and reveals that classical FRET architectures can harbor ultrafast through-bond channels of exciton deactivation.

Cite: Shekhovtsov N.A. , Bushuev M.B.
The Hidden Role of Through-Bond Energy Transfer in FRET-Dyes: A Quantum Dynamics Perspective
Journal of Physical Chemistry Letters. 2025. V.16. N35. P.9152–9158. DOI: 10.1021/acs.jpclett.5c02262 WOS OpenAlex

Dates:

Submitted:	Jul 22, 2025
Accepted:	Aug 21, 2025
Published online:	Aug 27, 2025
Published print:	Sep 4, 2025

Identifiers:

Web of science:	WOS:001559024200001
OpenAlex:	W4413759376

Citing: Пока нет цитирований

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