Twin states and conical intersections in linear polyenes

Fuß, Werner; Haas, Yehuda; Zilberg, Shmuel

doi:10.1016/s0301-0104(00)00200-7

Cited by 115 publications

(88 citation statements)

References 99 publications

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“…Since the cooling rate should depend only on the coupling between the solute and the solvent bath, the abovementioned 300-fs time constant cannot reflect cooling of the S 1 state. Instead, high-frequency structural rearrangement prior to internal conversion should be involved, as proposed by Fuß et al and Olivucci et al [23] In summary, we have reported broadband femtosecond optical spectra of all-trans b-carotene extending from the near-UV to the near-IR region. A damped oscillation with a period of approximately 350 fs appears with constant phase across the entire spectral window.…”

Section: Dod(tl)/ldlsupporting

confidence: 61%

S₂→S₁ Internal Conversion in β‐Carotene: Strong Vibronic Coupling from Amplitude Oscillations of Transient Absorption Bands

Lustres

Dobryakov

Holzwarth³

et al. 2007

Angew Chem Int Ed

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What happens next? Oscillatory dynamics during internal conversion of β‐carotene from the “bright” S2 to the “dark” S1 electronic state is observed by femtosecond broadband transient absorption and fluorescence. The spectral evolution was described quantitatively by modeling the quantum dynamics in a three‐level system, and the vibronic coupling element was determined (V≈95 cm−1).

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Section: Dod(tl)/ldlsupporting

confidence: 61%

S₂→S₁ Internal Conversion in β‐Carotene: Strong Vibronic Coupling from Amplitude Oscillations of Transient Absorption Bands

Lustres

Dobryakov

Holzwarth³

et al. 2007

Angew Chem Int Ed

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“…Regardless of geometry, ͉I͘ is dominated by the CSF with a doubly occupied imidazolinone ͑i͒ fragment orbital. Shaik and co-workers [73][74][75] to explain the presence of elevated vibrational frequencies in excited state of aromatics and linear polyenes 76 and by Zilberg and co-workers 72,77,78 in the prediction of locations of conical intersections. The idea is that for a resonant ground state of a given parity, the antiresonant ͑parity-reversed͒ superposition will describe a low-lying excited state.…”

Section: Energy Eigenstates In the Diabatic Representationmentioning

confidence: 99%

A diabatic three-state representation of photoisomerization in the green fluorescent protein chromophore

Olsen

McKenzie

2009

The Journal of Chemical Physics

122

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We give a quantum chemical description of the photoisomerization reaction of green fluorescent protein (GFP) chromophores using a representation over three diabatic states. Photoisomerization leads to non-radiative decay, and competes with fluorescence in these systems. In the protein, this pathway is suppressed, leading to fluorescence. Understanding the electronic states relevant to photoisomerization is a prerequisite to understanding how the protein suppresses it, and preserves the emitting state of the chromophore. We present a solution to the state-averaged complete active space problem, which is spanned at convergence by three fragment-localized orbitals. We generate the diabatic-state representation by block diagonalization transformation of the Hamiltonian calculated for the anionic chromophore model HBDI with multi-reference, multi-state perturbation theory. The diabatic states are charge-localized and admit a natural valence-bond interpretation. At planar geometries, the diabatic picture of the optical excitation reduces to the canonical two-state charge transfer resonance of the anion. Extension to a three-state model is necessary to describe decay via two possible pathways associated with photoisomerization of the (methine) bridge. Parametric Hamiltonians based on the three-state ansatz can be fit directly to data generated using the underlying active space. We provide an illustrative example of such a parametric Hamiltonian.

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“…In the carotenoid, the 160 cm À1 frequency can be identified with a b u mode that induces an angle alternation or bending of the CCC backbone. [38] Excursion along such an asymmetric coordinate is necessary to couple Car S 2 and S 1 or, more specifically, to reach a point where the C 2h symmetry is broken such that the electronic surfaces of Car S 2 and S 1 can cross via a conical intersection (Figure 10). [38] Selective excitation of the coupling b u mode facilitates IC and is thus responsible for the control of the energy flow ratio IC/EET.…”

Section: Interpretation Of Optimal Pulse Parametersmentioning

confidence: 99%

Coherent Control for Spectroscopy and Manipulation of Biological Dynamics

et al. 2005

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Motivated originally by the goal of steering a photoreaction into desired product channels, the concept of coherent control is to adapt the spectral and temporal characteristics of the excitation light to the inherent molecular resonances and dynamics, such that these can be selectively addressed and manipulated. In the last decade, the ultrafast dynamics of many atomic and molecular quantum systems in the gas and condensed phase have been controlled successfully. Motivations in chemistry are now 1) to perform spectroscopy by coherent control, which requires a deeper understanding of control mechanisms, 2) to treat more complex, biological photoreactions, and 3) the pragmatic use of coherent control techniques, for example, for pulse compression or enhanced contrast in multiphoton microscopy. As examples for 1) and 2) we review here the combined effort and interplay of conventional spectroscopy and coherent control experiments, applied to the energy flow in the light-harvesting complex LH2 from bacterial photosynthesis. Closed-loop control experiments allowed the characteristic coupling frequency of internal conversion in the carotenoid in LH2 to be extracted. Open-loop three-pulse control experiments, on the other hand, could directly observe an anticipated Raman-excited carotenoid ground state. As a variant of difference spectroscopy, coherent control has thus served to gain complementary spectroscopic knowledge about the energy flow in carotenoids by comparing natural to manipulated dynamics. Finally, we propose future coherent control experiments on the electronic state structure of carotenoids and discuss prospects of coherent control for other biological chromophores.

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Twin states and conical intersections in linear polyenes

Cited by 115 publications

References 99 publications

S₂→S₁ Internal Conversion in β‐Carotene: Strong Vibronic Coupling from Amplitude Oscillations of Transient Absorption Bands

S₂→S₁ Internal Conversion in β‐Carotene: Strong Vibronic Coupling from Amplitude Oscillations of Transient Absorption Bands

A diabatic three-state representation of photoisomerization in the green fluorescent protein chromophore

Coherent Control for Spectroscopy and Manipulation of Biological Dynamics

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Twin states and conical intersections in linear polyenes

Cited by 115 publications

References 99 publications

S2→S1 Internal Conversion in β‐Carotene: Strong Vibronic Coupling from Amplitude Oscillations of Transient Absorption Bands

S2→S1 Internal Conversion in β‐Carotene: Strong Vibronic Coupling from Amplitude Oscillations of Transient Absorption Bands

A diabatic three-state representation of photoisomerization in the green fluorescent protein chromophore

Coherent Control for Spectroscopy and Manipulation of Biological Dynamics

Contact Info

Product

Resources

About

S₂→S₁ Internal Conversion in β‐Carotene: Strong Vibronic Coupling from Amplitude Oscillations of Transient Absorption Bands

S₂→S₁ Internal Conversion in β‐Carotene: Strong Vibronic Coupling from Amplitude Oscillations of Transient Absorption Bands