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Time-Resolved X-Ray Spectroscopies and Scattering Spectroscopies and Scattering
with One Trillion Photons
Christian BresslerChristian Bressler
XDL Workshop “tickle and probe”, Cornell University, June 21, 2011
Dynamic Studies in Photochemistry
1. Intramolecular0 3
0,4
0,5
n / a
.u.
Ru(bpy)3 (aq)
Charge Transfer2835 2840 2845
0,0
0,1
0,2
0,3
Abs
orpt
ion
X-Ray Probe Energy / eVX Ray Probe Energy / eV
2. TowardsSolvation Dynamics 0,5
1,0
I-
I0
Abs
orpt
ion
/ a.u
.
F (b ) ( )
5180 5200 5220
0,0
X-Ray Probe Energy (eV)Nascent I0 (aq)
3. Light-InducedSpin Crossover
Fe(bpy)3 (aq)
Spin Crossover
What are the fundamental timescales?Chemistry and Biochemistry
Molecular
PhotosynthesisVision
S i M l l r R t ti n
Protein Folding
MolecularVibrations
P ti lStrings, Cosmology
Molecular Rotations
El d i
Particle Collisions
Electron dynamics
harpo10-27
yacto10-24
milli10-3
micro10-6
nano10-9
pico10-12
femto10-15
atto10-18
zepto10-21
Time /seconds
Now for the low-lying fruit (K edges)
1021=
10
1018
r S/N
RIXS, X-Ray Raman
1015
ons
for
Valence XESTransm
109
1012
Pho
to K XES
Fluorescence XAFS
ansmission XAFS
106
109
cide
nt XAFS
0,1 1 10 100 1000
10
Inc
,Aqueous Sample Concentation / mM
Towards Solvation Dynamics
-Distinguish IVR fromgguest-host interactions
-Example: NO/Rg matrixExample: NO/Rg matrix
Rydberg NO in rare gas matrices: bubble formation
Ultrafast Processes in the C nd n d Ph ( f n kind)
Speed of Sound: >10 Å/ps
Condensed Phase (of any kind)Speed of Sound: >10 Å/ps
100 1000 S l t M l l i l d…ca 100-1000 Solvent Molecules involved
X-Ray Absorption Spectroscopy X Ray Absorption Spectroscopy Singles Out Reaction Center ...
Electron Detachment Reactions (via XAFS)
1,0
n / a
.u.
2s→5p
0,0
0,5 I-
I0
Abs
orpt
ion
Pham et al., JACS (2007)
5180 5200 5220
X-Ray Probe Energy (eV)
I. Tavernelli (EPFL)Nascent I atoms in solution
EXAFS and XANES of nascent iodine radicals
static300 fs50 ps50 ps
50 ps
300 fs50 ps
50 psV.-T. Pham et al. Chem. Phys. (2010)
V.-T. Pham, PhD thesis (2010)
I0I-
V.-T. Pham et al. Submitted (2011)
I0
Now to something completely different….LS HS
10C. Consani et al.
Angew Chem (2009)
Towards Transient Structures via TR-XAFS
1
a.u.
01
LSA /
a
HS 50 ps
03
0
1
7100 7150
A x
1
∆RFe-N= 0.2 ±0.008 Å2 4 6 8 10
Photoelectron Wavevector k / Å-1
7100 7150
X-Ray Probe Energy / eV M. Benfatto (INFN Rome)
B0
1 t < 0
(k
) x k
2
B665 ps
1
-1
t = 50 ps
k2
Exp. (Ground State) Fit
70 ps0
(
k) x
k
Exp. (Transient) Fit
11 W. Gawelda et al. Phys. Rev. Lett. (2007)
W. Gawelda et al. J. Chem. Phys. (2009)
0 2 4 6 8 10-1
Photoelectron Wavevector k / Å-1
ps and fs XANES (Synchrotron)
u.1
LSA /
a.u
HS
0
A
50 ps
3
1
x 10
3 300 fs
0
A
7100 7150
X Ray Probe Energy / eV
X-Ray Probe Energy / eVC. Bressler et al., Science (2009)
Identifying intermediate states...
∆RF N =0.2 Å
y g
∆RFe-N 0.2 Å
-500 0 500 1000Time Delay / fs
250 fs (instrument response):
140(30) fs hard x-ray pulse115(10) fs laser pulse
10-12 photons/pulse (2 kHz, 2 eV BW)<100(30) fs time zero drifts
Combined optical and x-ray results
1MLCTb)??
120 fs
MLCT
y
3MLCT20 fs
)
<130 fs
Ene
rgy
E
5T (HS)2
665 ps
R (Fe-N)
1A (LS)1
Need now a Spin-Sensitive Tool !! Need now a Spin Sensitive Tool !!
Spin sensitivity e
IP3p
IP
2p
1s
Courtesy: Pieter Glatzel (ESRF)
1s XES of a spin transition molecule
1s2p 1s3p 1sVBexchange (J)
3dn p
1s
FeII— 3d6
S 0 2S = 0 2
T,p
hG. Vankó et al., J. Phys. Chem. B 110 (2006) 11647
h
Towards ultrafast X-ray Emission Spectroscopy
103 – 106 ph/pulse (100 ps) 10 12 ph/pulse (200 fs)10-12 ph/pulse (200 fs)10-3 ph/pulse (100 ps XES)
X S
a) b)D1D2
T = 960 nsX S
c)L c)D3
0 5
Ge(440)Laser 0.5 ms
G. Vankó et al., Angew. Chem. Int. Ed. (2010)
Direct spin probing: first TR-XES (ps)p p g (p )
Femtosecond Time Resolution Femtosecond Time Resolution Ideally suited for single wavelength
XFEL experiments MH titi t !!!! MHz repetition rates !!!!
G. Vanko et al., Angew. Chem. Int. Ed., (2010)
MHz Laser Installation at ESRF
Ready to Pump-Probe at MHz rep-rates!!Ready to Pump-Probe at MHz rep-rates!! 19
ID26 – X-ray Emission/Absorption Spectroscopy
201.4 MHz
ID26/ESRF (March 2011)( )
21
APS sector 7 (March 2011)APS, sector 7 (March 2011)
22
Picosecond K alpha XES at APS
1 kH t di t 1 kHz pp studies at SLS
(Angew Chem 2010)(Angew. Chem. 2010)
0 13 MHz at APS0.13 MHz at APS
23
back to the future:back to the future:
• Entering the femtosecond time scale (again)Linac coherent light source (LCLS)g ( )
• Credits: D. Fritz, M. Cammarata (SLAC)
XPP Commissioning (LCLS, Oct 2010) (Cammarata)
One single „File“ (10 min scan) at LCLSg ( )
Oct 2010: XPP commissioningg
SLS (t = 50 ps)SLS (t 300 f )
SLS (t = 50 ps)SLS (t 300 f )
0,1
S /
a.u.
SLS (t = 300 fs) XPP (t = 250 fs)
0,1
SLS (t = 300 fs) XPP (t 300 fs)
XA
NE
S
0,0
ansi
ent
0,0
Tra
7100 7110 7120 7130 7140 7150 7160
X-Ray Probe Energy / eV7100 7110 7120 7130 7140 7150 7160
X-Ray Probe Energy / eVy gyy gy
Real-Time Traces
n Science 2009
n Science 20090,003
sorp
tion Science 2009
Fit curve 2009 XPP 2010
0,003
sorp
tion Science 2009
Fit curve 2009 XPP 2010
0,002
sien
t Ab 0,002
sien
t Ab
0,001
ay T
rans 0,001
ay T
rans
0,000
X-R
a
0,000
X-R
a
-500 0 500 1000 1500-0,001
Laser-X-Ray Time Delay / fs-500 0 500 1000 1500
-0,001
Laser-X-Ray Time Delay / fsLaser X Ray Time Delay / fsLaser X Ray Time Delay / fs
Transient Spectra around Time Zero0,06
0,036
S
0,04
XAN
ES0,034
sien
t XA
NE
S
0,02
X
-500 0 500 1000
0,032Tran
s
0,0025
NE
S
0,00Laser X-Ray Time Delay / fs
1,0
1GS
0 0000ansi
ent X
AN
0,8
0,9
5 S1,3MLCTop
ulat
ion
0,0000Tr
a
0 0
0,1Spin Flip?
5HS, MLCTPo
7110 7120 7130 7140
X-Ray Probe Energy / eV
-500 0 500 10000,0
Time / fs
Looking into the raw data…
Summary of combined optical/XAS studies??
120 fseg
t
??
t2g
a)
1T1
1T21,3MLCT
y
)
1,3T…:<60 fs
15E
Ener
gy
3T1
3T2
1A1
R (Fe-N)
5T2
Need to include XES (spin) and even XRD (solvent)…experiments at APS/ESRF to prepare for LCLS
Next Step: Exploit Complementary Structural Tools(LCLS project 2011): Towards understanding chemical reactivity
XES: occupied DOS (spin)e- XES: occupied DOS (spin)
XAS: empty DOS (orbitals)
XRD: geometric structuresXRD: geometric structures
Collaboration:
M. Nielsen (Copenhagen)V S d t ö (L d)
1) Ru(II) Ru(III) (XAS XES optical)
V. Sundström (Lund)G. Vanko (Budapest)P. Glatzel (ESRF)
A M nt (P t 3)1) Ru(II) Ru(III) (XAS, XES, optical)
2) IVR + e-transport (XRD, optical)
3) Co(III) Co(II) (XAS XES optical)
A. Meents (Petra3)R. Abela (SwissFEL)
3) Co(III) Co(II) (XAS, XES, optical)
4) Co(II) LSHS (XAS, XES)
Conclusions
Towards Solvation Dynamics 0,5
1,0
I-
I0
Abso
rptio
n / a
.u.
y5180 5200 5220
0,0 I
X-Ray Probe Energy (eV)Nascent I0 (aq)
- We can follow the sequence of events from 300 fs onwardsqEven the (few) ps time scale we do not fully understand Theoretical input important
W d t k h thi l b t 0 300 f- We need to know how things evolve between 0-300 fs New experiments are planned (theory required)
Light-InducedSpin Crossover
Fe(bpy)3 (aq)
Spin Crossover
- We do not understand this correlated SCO behavior!…but we are already looking into the elementary steps !!!
AcknowledgmentsAcknowledgments 34
Argonne National Lab (APS)- Steven Southworth
University of Copenhagen- Martin Meedom Nielsen
- Anne-Marie March (MHz laser) - Gilles Doumy- Elliot Kanter
- Kristoffer HaldrupLund University
Villy Sundström Elliot Kanter- Dipanwita Ray- Robert Dunford- Linda Young
- Villy Sundström- Sophie Canton- Jens Uhlig
G i S l - Linda Young- Grigory SmolentsevKFKI Budapest- György VankóSwissFEL
R f l Ab l
ESRFPieter Glatzel
y gy- Rafael Abela
European XFEL Facility- Wojciech Gawelda- Pieter Glatzel
- Erik GalloWojciech Gawelda
- Andreas Galler
LCLS (SLAC) K. Gaffney, L. X. Chen, H. Ihee( )- David Fritz, Marco Cammarata
y, ,(XPP Oct 2010)