Ultrafast isomerization initiated by X-ray core ionization.
Rapid proton migration is a key process in hydrocarbon photochemistry. Charge migration and subsequent proton motion can mitigate radiation damage when heavier atoms absorb X-rays. If rapid enough, this can improve the fidelity of diffract-before-destroy measurements of biomolecular structure at X-ray-free electron lasers. Here we study X-ray-initiated isomerization of acetylene, a model for proton dynamics in hydrocarbons. Our time-resolved measurements capture the transient motion of protons following X-ray ionization of carbon K-shell electrons. We Coulomb-explode the molecule with a second precisely delayed X-ray pulse and then record all the fragment momenta. These snapshots at different delays are combined into a 'molecular movie' of the evolving molecule, which shows substantial proton redistribution within the first 12 fs. We conclude that significant proton motion occurs on a timescale comparable to the Auger relaxation that refills the K-shell vacancy.
Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, USA.|PULSE Institute for Ultrafast Energy Science, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
Chelsea E
CE
Liekhus-Schmaltz
Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, USA.|PULSE Institute for Ultrafast Energy Science, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
Ian
I
Tenney
Department of Physics, University of Connecticut, 2152 Hillside Road, Storrs, Connecticut 06269, USA.
Timur
T
Osipov
Department of Physics, Imperial College London, Prince Consort Road, London SW7 2AZ, UK.
Alvaro
http://orcid.org/0000-0001-5055-5790
A
Sanchez-Gonzalez
Department of Physics, University of Connecticut, 2152 Hillside Road, Storrs, Connecticut 06269, USA.
Nora
N
Berrah
Deutsches Elektronen-Synchrotron, Notkestrasse 85, 22607 Hamburg, Germany.|Max Planck Institute for Nuclear Physics, Saupfercheckweg 1, 69117 Heidelberg, Germany.
Rebecca
R
Boll
Deutsches Elektronen-Synchrotron, Notkestrasse 85, 22607 Hamburg, Germany.
Cedric
C
Bomme
Linac Coherent Light Source, 2575 Sand Hill Road, Menlo Park, California 94025.
Christoph
C
Bostedt
Linac Coherent Light Source, 2575 Sand Hill Road, Menlo Park, California 94025.
John D
JD
Bozek
Linac Coherent Light Source, 2575 Sand Hill Road, Menlo Park, California 94025.
Sebastian
S
Carron
Linac Coherent Light Source, 2575 Sand Hill Road, Menlo Park, California 94025.
Ryan
R
Coffee
Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, USA.|PULSE Institute for Ultrafast Energy Science, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
Julien
J
Devin
Deutsches Elektronen-Synchrotron, Notkestrasse 85, 22607 Hamburg, Germany.
Benjamin
B
Erk
Linac Coherent Light Source, 2575 Sand Hill Road, Menlo Park, California 94025.|Department of Applied Physics, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, USA.
Ken R
KR
Ferguson
Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
Robert W
RW
Field
Max Planck Institute for Medical Research, Jahnstrasse 29, 69120 Heidelberg, Germany.
Lutz
L
Foucar
Department of Physics, Imperial College London, Prince Consort Road, London SW7 2AZ, UK.
Leszek J
LJ
Frasinski
Linac Coherent Light Source, 2575 Sand Hill Road, Menlo Park, California 94025.
James M
JM
Glownia
PULSE Institute for Ultrafast Energy Science, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
Markus
M
Gühr
Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, USA.|PULSE Institute for Ultrafast Energy Science, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
Andrei
A
Kamalov
Linac Coherent Light Source, 2575 Sand Hill Road, Menlo Park, California 94025.
Jacek
J
Krzywinski
PULSE Institute for Ultrafast Energy Science, 2575 Sand Hill Road, Menlo Park, California 94025, USA.|Linac Coherent Light Source, 2575 Sand Hill Road, Menlo Park, California 94025.
Heng
H
Li
Department of Physics, Imperial College London, Prince Consort Road, London SW7 2AZ, UK.
Jonathan P
JP
Marangos
PULSE Institute for Ultrafast Energy Science, 2575 Sand Hill Road, Menlo Park, California 94025, USA.|Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, California 94305, USA.
Todd J
TJ
Martinez
PULSE Institute for Ultrafast Energy Science, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
Brian K
BK
McFarland
PULSE Institute for Ultrafast Energy Science, 2575 Sand Hill Road, Menlo Park, California 94025, USA.|Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, California 94305, USA.
Shungo
S
Miyabe
Department of Physics, University of Connecticut, 2152 Hillside Road, Storrs, Connecticut 06269, USA.
Brendan
B
Murphy
PULSE Institute for Ultrafast Energy Science, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
Adi
http://orcid.org/0000-0002-6594-7794
A
Natan
Deutsches Elektronen-Synchrotron, Notkestrasse 85, 22607 Hamburg, Germany.
Daniel
D
Rolles
Department of Physics, J. R. Macdonald Laboratory, Kansas State University, 306 Cardwell Hall, Manhattan, Kansas 66506, USA.
Artem
A
Rudenko
Department of Physics, Imperial College London, Prince Consort Road, London SW7 2AZ, UK.
Marco
M
Siano
Department of Physics, Imperial College London, Prince Consort Road, London SW7 2AZ, UK.
Emma R
ER
Simpson
Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, USA.|PULSE Institute for Ultrafast Energy Science, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
Limor
L
Spector
Linac Coherent Light Source, 2575 Sand Hill Road, Menlo Park, California 94025.
Michele
M
Swiggers
Department of Physics, Imperial College London, Prince Consort Road, London SW7 2AZ, UK.
Daniel
D
Walke
Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, USA.|PULSE Institute for Ultrafast Energy Science, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
Song
S
Wang
Lawrence Berkeley National Lab, 1 Cyclotron Road, Berkeley, California 94720, USA.
Thorsten
T
Weber
Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, USA.|PULSE Institute for Ultrafast Energy Science, 2575 Sand Hill Road, Menlo Park, California 94025, USA.|Department of Applied Physics, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, USA.
Philip H
PH
Bucksbaum
Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, California 94305, USA.|PULSE Institute for Ultrafast Energy Science, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
Vladimir S
VS
Petrovic