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Near-infrared time-resolved study of the S-1 state dynamics of the carotenoid spheroidene

Polivka, Tomas LU ; Zigmantas, Donatas LU ; Frank, H. A.; Bautista, J. A.; Herek, Jennifer LU ; Koyama, Y.; Fujii, R. and Sundström, Villy LU (2001) In The Journal of Physical Chemistry Part B 105(5). p.1072-1080
Abstract
Using a novel experimental approach based on near-infrared femtosecond absorption spectroscopy, we have determined the energy of the S-1 state of the carotenoid spheroidene. The energy of this state is 13 400 +/- 90 cm(-1) at both 293 and 186 K, showing that there is no temperature-induced shift of the S-1 level. A discrepancy of about 800 cm(-1) between the S-1 energy determined here and that obtained from previous fluorescence and resonance Raman measurements is explained in terms of the different conformational species coexisting in the S-1 excited state. Measurements of kinetics in the near-infrared region revealed that at least three relaxation processes take place after excitation of spheroidene into its S-2 state. Ultrafast S-2... (More)
Using a novel experimental approach based on near-infrared femtosecond absorption spectroscopy, we have determined the energy of the S-1 state of the carotenoid spheroidene. The energy of this state is 13 400 +/- 90 cm(-1) at both 293 and 186 K, showing that there is no temperature-induced shift of the S-1 level. A discrepancy of about 800 cm(-1) between the S-1 energy determined here and that obtained from previous fluorescence and resonance Raman measurements is explained in terms of the different conformational species coexisting in the S-1 excited state. Measurements of kinetics in the near-infrared region revealed that at least three relaxation processes take place after excitation of spheroidene into its S-2 state. Ultrafast S-2 --> S-1 internal conversion occurs within the first 300 fs, followed by vibrational cooling in the SI state, which occurs on a time scale of similar to 700 fs. The S-1 lifetime is 8 ps at 293 K, in good agreement with previous measurements of the S-1 --> S-N transition. A somewhat longer S-1 lifetime of 9.5 ps is observed at 186 K. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
long polyenes, crystal-structure, different extents, 2-photon fluorescence excitation, light-harvesting complex, rhodobacter-sphaeroides r-26.1, pi-electron conjugation, all-trans-spheroidene, xanthophyll cycle, energy-transfer
in
The Journal of Physical Chemistry Part B
volume
105
issue
5
pages
1072 - 1080
publisher
The American Chemical Society
ISSN
1520-5207
DOI
10.1021/jp002206s
language
English
LU publication?
yes
id
c391741e-3da7-4f75-8b89-70579ffa1cbf (old id 1432986)
date added to LUP
2009-07-01 12:13:47
date last changed
2016-04-16 06:32:20
@misc{c391741e-3da7-4f75-8b89-70579ffa1cbf,
  abstract     = {Using a novel experimental approach based on near-infrared femtosecond absorption spectroscopy, we have determined the energy of the S-1 state of the carotenoid spheroidene. The energy of this state is 13 400 +/- 90 cm(-1) at both 293 and 186 K, showing that there is no temperature-induced shift of the S-1 level. A discrepancy of about 800 cm(-1) between the S-1 energy determined here and that obtained from previous fluorescence and resonance Raman measurements is explained in terms of the different conformational species coexisting in the S-1 excited state. Measurements of kinetics in the near-infrared region revealed that at least three relaxation processes take place after excitation of spheroidene into its S-2 state. Ultrafast S-2 --> S-1 internal conversion occurs within the first 300 fs, followed by vibrational cooling in the SI state, which occurs on a time scale of similar to 700 fs. The S-1 lifetime is 8 ps at 293 K, in good agreement with previous measurements of the S-1 --> S-N transition. A somewhat longer S-1 lifetime of 9.5 ps is observed at 186 K.},
  author       = {Polivka, Tomas and Zigmantas, Donatas and Frank, H. A. and Bautista, J. A. and Herek, Jennifer and Koyama, Y. and Fujii, R. and Sundström, Villy},
  issn         = {1520-5207},
  keyword      = {long polyenes,crystal-structure,different extents,2-photon fluorescence excitation,light-harvesting complex,rhodobacter-sphaeroides r-26.1,pi-electron conjugation,all-trans-spheroidene,xanthophyll cycle,energy-transfer},
  language     = {eng},
  number       = {5},
  pages        = {1072--1080},
  publisher    = {ARRAY(0x95627b8)},
  series       = {The Journal of Physical Chemistry Part B},
  title        = {Near-infrared time-resolved study of the S-1 state dynamics of the carotenoid spheroidene},
  url          = {http://dx.doi.org/10.1021/jp002206s},
  volume       = {105},
  year         = {2001},
}