Spin Chemical Control of Photoinduced Electron-Transfer Processes in Ruthenium(II)-Trisbipyridine-Based Supramolecular Triads J. Am. Chem. Soc. 1999, 121, 1076−1087

Abstract

Page 1087, footnote 72: The value of the quantum efficiency for charge separation reported as φ cs ) 0.86 ( 0.08% is incorrect. The correct value is 86 ( 8%.

Intramolecular Spin Alignment within Mono‐Oxidized and Photoexcited Anthracene‐Based π Radicals as Prototypical Photomagnetic Molecular Devices: Relationships Between Electrochemical, Photophysical, and Photochemical Control Pathways

“…These functional assemblies, namely, light-triggered donors of spin-polarized electrons ( [74] by relying on exchange interactions within "spincompatible" (IET allowed) and "spin-incompatible" (IET forbidden) associations of proper "spin-selective" D/D*-Rad and A-Rad components.…”

Spin Relaxation in Ru‐Chromophore‐Linked Azine/Diquat Radical Pairs

“…11 Detailed models of the energetics and kinetics of the CSS formation and decay back to the ground state in these specific DCA triad systems have been provided earlier. [11][12][13][14][15][16][17][18][19][20][21] Ru II Of particular relevance to the present discussion is the observation that the CSS, which is a biradical cation, is formed with essentially pure triplet spin correlation. 12 For energetic reasons, this triplet radical pair cannot recombine to form the 3 MLCT state and can only form the singlet ground state.…”

“…22 Scheme 10.1 shows how this model is applied to the DCA triad CSS under consideration. 12,23 The reduced diquat acceptor and oxidized azine donor are "normal" organic radicals that can physically separate within CSS to at least 20 A . Therefore, at zero applied magnetic field, the triplet CSS ( 3 CS) and singlet CSS ( 1 CS) are nearly degenerate and isotropic hyperfine coupling provides a path to mix these states allowing for CSS decay.…”

“…The path to the ground state for the T 0 state remains unchanged while at small fields the splitting of the field dependent states exceeds the hyperfine coupling energy, thus diminishing singlet-triplet mixing from those states and retarding their rate of decay to the ground state. 12 The model in Scheme 10.1 suggests that application of a magnetic field to the CSS should result in biexponential decay kinetics consisting of a field independent (T 0 ) portion along with a field dependent portion (T À and T þ ). Within the CSS of these DCA triads the oxidized donor and the reduced acceptor each exhibit intense, isolated…”

“…With zero applied magnetic field, the decay of the CSS to the ground state is approximately monoexponential (t ¼ 100 ns). 12,23 Upon application of an external magnetic field, the decay becomes distinctly biexponential with a field dependent portion and a field independent portion. This result is a clear demonstration of the applicability of the model in Scheme 10.1 to the DCA system.…”