Picosecond molecular switch based on the influence of photogenerated electric fields on optical charge transfer transitions

Just, Eric M.; Wasielewski, Michael R.

doi:10.1006/spmi.2000.0919

Cited by 21 publications

(17 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Photoexcitation of 6PMI in 2 with laser pulses with a wavelength of 510 nm (510‐nm pulse) results in the charge separation (CS) reaction TMPD‐ 1 *6PMI→TMPD + ‐6PMI − with a 1/ e time of τ =18 ps followed by the charge recombination (CR) reaction TMPD + ‐6PMI − →TMPD‐6PMI with τ =55 ps. The course of the reaction is followed using the absorption of the radical anion of 6PMI − at 645 nm 13. 22 The reduction potential of PI is −0.79 V versus SCE and the oxidation potential of ZnP is 0.72 V versus SCE, so that Δ G CS ≅−0.2 eV in toluene.…”

Section: Methodsmentioning

confidence: 99%

Bio‐Inspired Optically Controlled Ultrafast Molecular AND Gate

et al. 2003

View full text Add to dashboard Cite

A fast switch: A covalent molecular tetrad (see picture), consisting of two electron donor/acceptor pairs acts as a high‐speed molecular AND gate when it is sequentially excited using laser pulses having two different wavelengths. This system of using two sequential photodriven electron transfers is analogous to photosystems I and II in green plants which act in series to separate charge for long periods of time.

show abstract

Section: Methodsmentioning

confidence: 99%

Bio‐Inspired Optically Controlled Ultrafast Molecular AND Gate

et al. 2003

View full text Add to dashboard Cite

show abstract

“…Previous work from our laboratory has explored the advantages of using perylene imides and diimides as photochemically robust, electronically wellcharacterized chromophores for energy and electron transfer studies. [3][4][5][6][7][8][9][10][11][12] For example, we have studied the effect of substituting the 1 and 7 positions of 3,4:9, 10-perylenebis(dicarboximide) with pyrrolidine via its nitrogen atom. 4 This molecule (5PDI) exhibits a strong charge transfer (CT) transition resulting from donation of electron density from the pyrrolidine nitrogen atom lone pair into the perylene core.…”

Section: Introductionmentioning

confidence: 99%

Ultrafast Charge Separation Due to Excited State Symmetry Breaking in Dimers of Push‐Pull Perylenes

Fuller

Гусев

Wasielewski

2004

Israel Journal of Chemistry

View full text Add to dashboard Cite

Photoexcitation of chromophoric dimers constrained to a symmetric π-stacked geometry by their molecular structure usually produce excimers independent of solvent polarity, while dimers with edge-to-edge perpendicular π systems undergo excited-state symmetry breaking in highly polar solvents leading to intradimer charge separation. We present direct evidence for symmetry breaking in the lowest excited singlet state of a symmetric cofacial dimer of 9-(N-pyrrolidinyl)-1,6-bis(3,5-di-tert-butylphenoxy)perylene-3,4-dicarboximide (5PMI) in the lowpolarity solvent toluene to produce a radical ion pair quantitatively. This dimer, cof-5PMI 2 , was synthesized by attaching two 5PMI chromophores via imide groups to a xanthene spacer. For comparison, a linear symmetric dimer, lin-5PMI 2 , was prepared in which the 5PMI chromophores are linked end-to-end via a N-N single bond between their imides. The edge-to-edge π systems of the 5PMI chromophores within lin-5PMI 2 are perpendicular to one another. Ground-state absorption spectra of both 5PMI dimers show exciton coupling, which is consistent with the orientation of the 5PMI chromophores relative to one another. Ultrafast transient absorption spectroscopy following excitation of the dimers with 400-nm, 80-fs laser pulses shows that quantitative intradimer electron transfer occurs in cof-5PMI 2 in toluene with τ = 0.9 ps, followed by charge recombination to ground state with τ = 780 ps. Similar measurements on lin-5PMI 2 reveal that photoinduced electron transfer does not occur in toluene, but occurs in more polar solvents such as 2-methyltetrahydrofuran, wherein τ = 4.5 ps for charge separation and τ = 660 ps for charge recombination. Excited-state symmetry breaking in 5PMI dimers provides new routes to biomimetic charge separation and storage assemblies that can be more easily prepared and modified than those based on multiple tetrapyrrole macrocycles.

show abstract

“…systems thus involve internal transfers of optical excitation energy, the RET activated by an applied electric 29,30 or optical field [31][32][33][34][35] for example. Such devices hold significant promise for the furtherance of ultrafast communication and signal processing systems.…”

Section: Optical Control Of Energy Transfermentioning

confidence: 99%

Theory of directed transportation of electronic excitation between single molecules through photonic coupling

Andrews

2008

SPIE Proceedings

View full text Add to dashboard Cite

The primary result of UV-Visible photon absorption by complex organic molecules is the population of short-lived electronic excited states. Transportation of their excitation energy between single molecules, formally mediated by near-field interactions, may occur between the initial absorption and eventual fluorescence emission events, commonly on an ultrafast timescale. The routing of energy flow is typically effected by a sequence of pairwise transfer steps over numerous molecules, rather than a single step over the same overall distance. Directionality emerges when there is structure in the molecular organisation. For a chemically heterogeneous system with local order, and with suitable molecular dispositions, automatically unidirectional transfer can be exhibited as the result of a 'spectroscopic gradient'. However it is also possible to exert control over the directionality of excitation flow by the operation of external influences. Examples are the application of an electrical or optical stimulus to the system -achieved by the incorporation of an ancillary polar species, the application of a static electric field or electromagnetic radiation. Most significantly, based on the latter option, an all-optical method has recently been determined that enables excitation transportation to be completely switched on or off, such that the energy flow is subject to controllable photoactivated gating. It is already apparent that this photonic process, termed Optically Controlled Resonance Energy Transfer, has potentially numerous applications. For example, it represents a new basis for optical transistor action.

show abstract

Picosecond molecular switch based on the influence of photogenerated electric fields on optical charge transfer transitions

Cited by 21 publications

References 22 publications

Bio‐Inspired Optically Controlled Ultrafast Molecular AND Gate

Bio‐Inspired Optically Controlled Ultrafast Molecular AND Gate

Ultrafast Charge Separation Due to Excited State Symmetry Breaking in Dimers of Push‐Pull Perylenes

Theory of directed transportation of electronic excitation between single molecules through photonic coupling

Contact Info

Product

Resources

About