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Environment. Laser. Projectile. Time-resolved dynamics. Dynamics of clusters and molecules in strong electromagnetic fields: A TDDFT-MD approach. Fondamental studies of mechanisms of irradiation and response of clusters coupled with environment. Ionization. Methods on the market.
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Environment Laser Projectile Time-resolved dynamics Dynamics of clusters and molecules in strong electromagnetic fields: A TDDFT-MD approach Fondamental studies of mechanisms of irradiation and response of clusters coupled with environment Ionization
Methods on the market Today: CNOH molecules + H2O "environment" Nan@Ar,Ne,Kr @ MgO Dynamics TDDFT-MD Gen. QM/MM Dyn. polar. Environment Electrons TDCI Car-Parinello, BO QM/MM Car-Parinello, BO/MD model-potential electrons model-potential electrons Statics
MD-TDDFT(LDA) TDDFT-MD Nan n valence e- Today, ions are: C4+, O6+, N7+, H+ laser projectile TDLDA + ADSIC non-adiab. dynamics (≠BO) n ions (Na+) • explicit • pseudopotentials
Numerical details Home-made codes represented on 3D grid: 483, 643, 723, 963, … propagation: time-splitting Verletalgorithm Goedecker-like (non-local) dt = 0.5 as box size fixed ions moving ions 50 fs for H2O
(Time-resolved) observables from electrons: • optical response • cloud deformation, shape, localization • ionization • number of emitted e- • kinetic E spectrum of emitted e- • angular distribution of emitted e- • level depletion • potential and kinetic (temperature) E • global deformation and shape • bond lengths, energies from ions: • Today: • projectile + H2O • laser + (H2O) H3O+ • laser/proj. + C2H4
charge velocity 0 Why TDLDA-MD ? projectile + H2O water = electronic insulator gap 10 eV threshold sudden cf. J. Kohanoff adiab. 0.1 au
charge velocity 0 Why TDLDA-MD ? • Which theory for: • dynamical description of • irradiation and response of • electrons and ions ? sudden e- TDDFT + fixed ions ? H+ + H2O ? adiab. "fixed e-" + ionic MD ? C + H2O
Laser irradiation of (H2O)H3O+ off-resonant but... vibrations I0=1013W/cm2 FWHM=20 fs frequency scan off-resonant Epol IP=-20.6 eV 2
C2H4 : optical response 6.8 eV IP: -11.7 eV Fourier Transform 8.16 eV 136 eV Yabana, Bertsch (2001)
C2H4 : laser irradiation I = 1013 Wcm-2 FWHM = 20 fs Laser pol. below resonances on resonance well above resonance
C2H4 : ionization mechanisms Ionization (level depletion) from a given electronic level Compare cases with similar (small) net ionization
Environment Laser Projectile Time resolved dynamics Ionization Time resolved dynamics Key importance of non adiabatic electron-ion dynamics for understanding mechanisms Dynamical description of irradiation and response of electrons and ions with coupling to environment • Environment • Hierarchical model • Dynamical QM/MM • - Na@Ar, Kr, Ne • - Na @ MgO • - Na@H2O in the oven • - C, N, O @ H2O in near future • - C, N, O @ H2O @Ar in future Thanks to E. Suraud, P.-G. Reinhard, Z.P. Wang, U. Ndongmouo, J. Messud S. Vidal, and you for your attention ! Irradiation of clusters and molecules by intense electro- magnetic fields Dynamics of ionization - Self Interaction problem (SIC) - Benchmark TDSIC calculations - Simple approximations in the oven - Dynamical correlations in the future (electronic transport)