Through-space and through-bond effects on exciton interactions in rigidly linked dinaphthyl molecules

Enhanced Two‐Photon Absorption of Organic Chromophores: Theoretical and Experimental Assessments

“…This observation suggests that not only dipolar interactions but also coherent interactions mediated by substantial wavefunction overlaps, [299,301] are important in defining the total coupling values and, hence, the spectroscopic properties of branched structures. [120] While triphenylamine center is able to promote this kind of coupling, the TPB core is not able to do so.…”

“…[120] This means that coherent interactions between branches and higher-lying excited states (beyond the Frenkel exciton model) [298][299][300][301] are important in order to interpret the TPA enhancement in the branched structure. [113] Interbranch coupling not only induces shifts of the one-and two-photon absorption bands, but also results in strong TPA enhancement in the whole relevant spectral region.…”

“…These characteristics determine the nature and the strength of the interbranch coupling that can be purely electrostatic or contain other contributions such as coherent interactions. [299,300] In addition, TPA broadening can occur from the inherent symmetry breaking of the sub-chromophores and from a larger number of close excited states which give rise to overlap of TPA bands originating from different states.…”

Analytical strategies based on quantum dots for heavy metal ions detection

“…70 (2) DET, which goes by a through-bond mechanism. 69 The Dexter mechanism 71 requires direct donor-acceptor orbital overlap and has an exponential-distance dependence with a range of approximately 1 nm. Based on one or the other of the described energy transfer mechanisms, several QD-based systems have been developed for the sensing of heavy metal ions.…”

Principles of Directed Electronic Energy Transfer

“…This form of energy transfer involves a donor exchanging its excited electron with an unexcited one from an acceptor. Even if the donor and acceptor are separated beyond wavefunction overlap, electron exchange may still occur via a super-exchange mechanism [9][10][11][12], in which the coupling of the pair operates through a delocalization or mixing of the chromophore wavefunctions with those of bridging species (relay chromophores), connecting bonds or the local solvent cage. Energy transfer may thus be further directed between chromophores linked by suitable intermediaries.…”