Self-terminating diffraction gates femtosecond X-ray nanocrystallography measurements.
X-ray free-electron lasers have enabled new approaches to the structural determination of protein crystals that are too small or radiation-sensitive for conventional analysis1. For sufficiently short pulses, diffraction is collected before significant changes occur to the sample, and it has been predicted that pulses as short as 10 fs may be required to acquire atomic-resolution structural information1-4. Here, we describe a mechanism unique to ultrafast, ultra-intense X-ray experiments that allows structural information to be collected from crystalline samples using high radiation doses without the requirement for the pulse to terminate before the onset of sample damage. Instead, the diffracted X-rays are gated by a rapid loss of crystalline periodicity, producing apparent pulse lengths significantly shorter than the duration of the incident pulse. The shortest apparent pulse lengths occur at the highest resolution, and our measurements indicate that current X-ray free-electron laser technology5should enable structural determination from submicrometre protein crystals with atomic resolution.
Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany.
Anton
A
Barty
Carl
C
Caleman
Andrew
A
Aquila
Nicusor
N
Timneanu
Lukas
L
Lomb
Thomas A
TA
White
Jakob
J
Andreasson
David
D
Arnlund
Saša
S
Bajt
Thomas R M
TR
Barends
Miriam
M
Barthelmess
Michael J
MJ
Bogan
Christoph
C
Bostedt
John D
JD
Bozek
Ryan
R
Coffee
Nicola
N
Coppola
Jan
J
Davidsson
Daniel P
DP
Deponte
R Bruce
RB
Doak
Tomas
T
Ekeberg
Veit
V
Elser
Sascha W
SW
Epp
Benjamin
B
Erk
Holger
H
Fleckenstein
Lutz
L
Foucar
Petra
P
Fromme
Heinz
H
Graafsma
Lars
L
Gumprecht
Janos
J
Hajdu
Christina Y
CY
Hampton
Robert
R
Hartmann
Andreas
A
Hartmann
Günter
G
Hauser
Helmut
H
Hirsemann
Peter
P
Holl
Mark S
MS
Hunter
Linda
L
Johansson
Stephan
S
Kassemeyer
Nils
N
Kimmel
Richard A
RA
Kirian
Mengning
M
Liang
Filipe R N C
FR
Maia
Erik
E
Malmerberg
Stefano
S
Marchesini
Andrew V
AV
Martin
Karol
K
Nass
Richard
R
Neutze
Christian
C
Reich
Daniel
D
Rolles
Benedikt
B
Rudek
Artem
A
Rudenko
Howard
H
Scott
Ilme
I
Schlichting
Joachim
J
Schulz
M Marvin
MM
Seibert
Robert L
RL
Shoeman
Raymond G
RG
Sierra
Heike
H
Soltau
John C H
JC
Spence
Francesco
F
Stellato
Stephan
S
Stern
Lothar
L
Strüder
Joachim
J
Ullrich
X
X
Wang
Georg
G
Weidenspointner
Uwe
U
Weierstall
Cornelia B
CB
Wunderer
Henry N
HN
Chapman