Imperial College London
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ProfessorJaspervan Thor

Faculty of Natural Sciences, Department of Life Sciences

Professor of Molecular Biophysics
 
 
 
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Contact

 

+44 (0)20 7594 5071j.vanthor Website

 
 
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Location

 

703Sir Ernst Chain BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Hutchison:2017:10.1080/0144235X.2017.1276726,
author = {Hutchison, CDM and van, Thor JJ},
doi = {10.1080/0144235X.2017.1276726},
journal = {International Reviews in Physical Chemistry},
pages = {117--143},
title = {Populations and coherence in femtosecond time resolved X-ray crystallography of the photoactive yellow protein},
url = {http://dx.doi.org/10.1080/0144235X.2017.1276726},
volume = {36},
year = {2017}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Ultrafast X-ray crystallography of the photoactive yellow protein with femtosecond delays using an X-ray free electron laser has successfully probed the dynamics of an early Franck-Condon species. The femtosecond pump-probe application of protein crystallography represents a new experimental regime that provides an X-ray structural probe for coherent processes that were previously accessible primarily using ultrafast spectroscopy. We address how the optical regime of the visible pump, that is necessary to successfully resolve ultrafast structural differences, affects the motions that are measured using the technique. The sub-picosecond photochemical dynamics in PYP involves evolution of a mixture of electronic ground and excited state populations. Additional to photoisomerisation that is considered to proceed through activated barrier crossing, within the dephasing time structural motion include vibrational coherence arising from excited states, the ground state and a ground state intermediate under experimental conditions used for ultrafast crystallography. Intense optical pulses are required to convert population levels in PYP crystals that allow detection by X-ray crystallography, but the compromise currently needed for the optical bandwidth and power has consequences with regard to the contributions to the motions that are experimentally measured with femtosecond delays. We briefly review the ultrafast spectroscopy literature of the primary photoreactions of PYP and discuss relevant physical models taken from coherent control and femtosecond coherence spectroscopy literature that address both the population transfer as well as the vibrational coherences. We apply linear response theory, with the additional use of a high power approximation, of on-resonance impulsive vibrational coherence in the ground state and the non-impulsive coherence in the excited state and discuss experimental approaches to manipulate the coherence contributions. The results are generalis
AU  - Hutchison,CDM
AU  - van,Thor JJ
DO  - 10.1080/0144235X.2017.1276726
EP  - 143
PY  - 2017///
SN  - 0144-235X
SP  - 117
TI  - Populations and coherence in femtosecond time resolved X-ray crystallography of the photoactive yellow protein
T2  - International Reviews in Physical Chemistry
UR  - http://dx.doi.org/10.1080/0144235X.2017.1276726
UR  - http://hdl.handle.net/10044/1/45807
VL  - 36
ER  -
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