%0 Journal Article
%@ 1948-7185
%A Greenwood, JB
%A Miles, J
%A De Camillis, S
%A Mulholland, P
%A Zhang, L
%A Parkes, MA
%A Hailes, HC
%A Fielding, HH
%D 2014
%F discovery:1456387
%J JOURNAL OF PHYSICAL CHEMISTRY LETTERS
%N 20
%P 3588 - 3592
%T Resonantly Enhanced Multiphoton Ionization Spectrum of the Neutral Green Fluorescent Protein Chromophore
%U https://discovery-pp.ucl.ac.uk/id/eprint/1456387/
%V 5
%X The photophysics of the green fluorescent protein is governed by the electronic structure of the chromophore at the heart of its β-barrel protein structure. We present the first two-color, resonance-enhanced, multiphoton ionization spectrum of the isolated neutral chromophore in vacuo with supporting electronic structure calculations. We find the absorption maximum to be 3.65 ± 0.05 eV (340 ± 5 nm), which is blue-shifted by 0.5 eV (55 nm) from the absorption maximum of the protein in its neutral form. Our results show that interactions between the chromophore and the protein have a significant influence on the electronic structure of the neutral chromophore during photoabsorption and provide a benchmark for the rational design of novel chromophores as fluorescent markers or photomanipulators.
%Z This is an open access article published under a Creative Commons Attribution (CC-BY) License, which permits unrestricted use, distribution and reproduction in any medium, provided the author and source are cited.