Dynamics of irradiated clusters and molecules

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• Irradiation of solvated
•  bio molecules
• Microscopic mechanisms
• - Role of water environment
• Medical applications
• Society applications

Dynamics of irradiatedclusters and
molecules

• Laser irradiations of
• free clusters
• Huge energy absorption in
• intense laser fields
• Production of energetic
• electrons, ions, photons
• - Many-body  laboratory 
• Time resolved dynamics

Deposited/embedded species - Shaping at
nanoscale - Defect formation - Chromophore
effects and therapy applications
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Specifications
Dynamical description of irradiation and
response of - Electrons - Ions - Environment
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Example Na9 laser
Laser intensity
Laser polarization
? 0
I 5. 1011 W.cm-2 Pulse in cos2 Delay 50
fs FWHM 125 fs w 2.3 eV
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Model (cluster/molecule)
? Electrons
? Local Density Approximation (LDA)
Self Interaction Correction (SIC)
? Semi-classical theory available (Vlasov, VUU)
? Ions
? Explicit ions via pseudo potentials ? Detail of
structure ionic Molecular Dynamics (MD)
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Model (cluster/molecule)
? Electrons
fs ps
? Local Density Approximation (LDA)
Self Interaction Correction (SIC)
? Semi-classical theory available (Vlasov, VUU)
? Ions
? Explicit ions via pseudo potentials ? Detail of
structure ionic Molecular Dynamics (MD)
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Observables
? Electrons
? Excitation energy
? Ions
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Electron emission from irradiated clusters
ds/dE
s ( w )
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Electron emission from irradiated clusters
Electron emission from irradiated clusters
ds/dE
ds/dW
Photon energy
Laser
s ( w )
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Electron emission from irradiated clusters
Electron emission from irradiated clusters
ds/dE
Time resolved dynamics
ds/dW
III
II
Photon energy
Laser
FEL lasers
s ( w )
Energy resol. angul. distri.
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Energy resolved angular distributions
Angle-energy correlation ? ds/dWdE
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Energy resolved angular distributions
The orientation Problem
Angle-energy correlation ? ds/dWdE
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Electron emission from irradiated clusters
Electron emission from irradiated clusters
ds/dE
Time resolved dynamics
ds/dW
III
II
Photon energy
Laser
FEL lasers
s ( w )
Energy resol. angul. distri.
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Ethylene in laser fields
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Electron emission from irradiated clusters
Electron emission from irradiated clusters
ds/dE
Time resolved dynamics
ds/dW
III
II
Photon energy
Laser
FEL lasers
s ( w )
Energy resol. angul. distri.
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Electron emission from irradiated clusters
Electron emission from irradiated clusters
ds/dE
Time resolved dynamics
ds/dW
III
II
Photon energy
Laser
FEL lasers
s ( w )
Energy resol. angul. distri.
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Electron emission from irradiated clusters
Electron emission from irradiated clusters
ds/dE
Time resolved dynamics
ds/dW
III
Photon energy
Laser
s ( w )
Energy resol. angul. distri.
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Electron emission from irradiated clusters
Electron emission from irradiated clusters
ds/dE
Time resolved dynamics
Yield
Optical Response
ds/dW
III
Photon energy
Laser
s ( w )
Energy resol. angul. distri.
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Electron emission from irradiated clusters
Electron emission from irradiated clusters
ds/dE
Time resolved dynamics
Yield
Optical Response
ds/dW
III
Photon energy
Laser
s ( w )
Energy resol. angul. distri.
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 Pump probe for vibration
Strong
Ionization maps Vibrations
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Monopole  Pump Probe  Dynamics
Ionization as a function of delay between pump
and probe laser pulses
? Ionic vibration period ? Expansion rate
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• Environment
• Hierarchical model
• Dynamical QM/MM
• - Na_at_Ar, Kr, Ne done
• - Na _at_ MgO done
• - Na_at_H2O in the oven
• - C, N, O _at_ H2O in near future
• - C, N, O _at_ H2O _at_Ar in future

Solvated molecules
Irradiation of clusters and molecules

• Time resolved dynamics
• Key importance of non adiabatic
• electron/ion couplings
• Photoelectron spectroscopy
• energy, angle done/ in the oven
• - Pump and probe scenarios done
• FEL laser domain in the oven
• Collisional scenarios in near future
• Atto laser domain in the oven

Dynamical description of irradiation and
response of - electrons - ions - environment
Free clusters
Dynamics of ionization in TDDFT - Self
Interaction problem (SIC) - Benchmark TDSIC
calculation done - Simple approximations in the
oven - Dynamical correlations in the future
(electronic transport)
Signals from electrons
People P. M. Dinh, P. G. Reinhard, ES, Z. Wang
Electron Emission
Deposited clusters
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Example of collision Na9 Ar 8
E 2.32 keV b 20 a0
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