Dynamic band-shift signal in two-dimensional electronic spectroscopy : A case of bacterial reaction center
(2021) In Journal of Chemical Physics 154(11).- Abstract
Optical nonlinear spectroscopies carry a high amount of information about the systems under investigation; however, as they report polarization signals, the resulting spectra are often congested and difficult to interpret. To recover the landscape of energy states and physical processes such as energy and electron transfer, a clear interpretation of the nonlinear signals is prerequisite. Here, we focus on the interpretation of the electrochromic band-shift signal, which is generated when an internal electric field is established in the system following optical excitation. Whereas the derivative shape of the band-shift signal is well understood in transient absorption spectroscopy, its emergence in two-dimensional electronic spectroscopy... (More)
Optical nonlinear spectroscopies carry a high amount of information about the systems under investigation; however, as they report polarization signals, the resulting spectra are often congested and difficult to interpret. To recover the landscape of energy states and physical processes such as energy and electron transfer, a clear interpretation of the nonlinear signals is prerequisite. Here, we focus on the interpretation of the electrochromic band-shift signal, which is generated when an internal electric field is established in the system following optical excitation. Whereas the derivative shape of the band-shift signal is well understood in transient absorption spectroscopy, its emergence in two-dimensional electronic spectroscopy (2DES) has not been discussed. In this work, we employed 2DES to follow the dynamic band-shift signal in reaction centers of purple bacteria Rhodobacter sphaeroides at 77 K. The prominent two-dimensional derivative-shape signal appears with the characteristic formation time of the charge separated state. To explain and characterize the band-shift signal, we use expanded double-sided Feynman diagram formalism. We propose to distinguish two types of Feynman diagrams that lead to signals with negative amplitude: excited state absorption and re-excitation. The presented signal decomposition and modeling analysis allows us to recover precise electrochromic shifts of accessory bacteriochlorophylls, identify additional signals in the B band range, and gain a further insight into the electron transfer mechanism. In a broader perspective, expanded Feynman diagram formalism will allow for interpretation of all 2D signals in a clearer and more intuitive way and therefore facilitate studying the underlying photophysics.
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- author
- Bukartė, Eglė LU ; Paleček, David LU ; Edlund, Petra ; Westenhoff, Sebastian LU and Zigmantas, Donatas LU
- organization
- publishing date
- 2021
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of Chemical Physics
- volume
- 154
- issue
- 11
- article number
- 115102
- publisher
- American Institute of Physics (AIP)
- external identifiers
-
- scopus:85102850418
- pmid:33752351
- ISSN
- 0021-9606
- DOI
- 10.1063/5.0033805
- language
- English
- LU publication?
- yes
- id
- 3363cd7d-848e-40a6-8cf7-2500b23ecb2e
- date added to LUP
- 2021-03-30 14:07:39
- date last changed
- 2024-09-21 18:00:31
@article{3363cd7d-848e-40a6-8cf7-2500b23ecb2e, abstract = {{<p>Optical nonlinear spectroscopies carry a high amount of information about the systems under investigation; however, as they report polarization signals, the resulting spectra are often congested and difficult to interpret. To recover the landscape of energy states and physical processes such as energy and electron transfer, a clear interpretation of the nonlinear signals is prerequisite. Here, we focus on the interpretation of the electrochromic band-shift signal, which is generated when an internal electric field is established in the system following optical excitation. Whereas the derivative shape of the band-shift signal is well understood in transient absorption spectroscopy, its emergence in two-dimensional electronic spectroscopy (2DES) has not been discussed. In this work, we employed 2DES to follow the dynamic band-shift signal in reaction centers of purple bacteria Rhodobacter sphaeroides at 77 K. The prominent two-dimensional derivative-shape signal appears with the characteristic formation time of the charge separated state. To explain and characterize the band-shift signal, we use expanded double-sided Feynman diagram formalism. We propose to distinguish two types of Feynman diagrams that lead to signals with negative amplitude: excited state absorption and re-excitation. The presented signal decomposition and modeling analysis allows us to recover precise electrochromic shifts of accessory bacteriochlorophylls, identify additional signals in the B band range, and gain a further insight into the electron transfer mechanism. In a broader perspective, expanded Feynman diagram formalism will allow for interpretation of all 2D signals in a clearer and more intuitive way and therefore facilitate studying the underlying photophysics. </p>}}, author = {{Bukartė, Eglė and Paleček, David and Edlund, Petra and Westenhoff, Sebastian and Zigmantas, Donatas}}, issn = {{0021-9606}}, language = {{eng}}, number = {{11}}, publisher = {{American Institute of Physics (AIP)}}, series = {{Journal of Chemical Physics}}, title = {{Dynamic band-shift signal in two-dimensional electronic spectroscopy : A case of bacterial reaction center}}, url = {{http://dx.doi.org/10.1063/5.0033805}}, doi = {{10.1063/5.0033805}}, volume = {{154}}, year = {{2021}}, }