Control and Imaging of processes triggered by X-ray pulses in multi-center molecules

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Attoscience is one of the great scientific challenges of the 21st century. While femtosecond laser pulses provided a candid camera into the world of nuclear motion, attosecond laser pulses will bring a revolution in our understanding of electron dynamics. Attoseconds and sub-femtoseconds are the natural time scale for multi-electron effects during complete ionization and break-up of atoms and molecules. Attosecond ``steering" of electrons in chemical bonds using ultra-short pulses is a fundamental way of manipulatingthe molecular structure. Controlling the electronic motion in small molecules will pave the way for modifyingthe structure of complex biomolecules, thus impacting such diverse fields as physics, chemistry and biology. The overall aim of the proposed work is to harness the properties of ultra-short and ultra-strong laser pulses to time-resolve and control attosecond phenomena triggered by intense X-ray laser pulses in multi-center molecular systems. The rapid experimental advances make urgent the quest for new theoretical tools that will address the challenges facing Attoscience. The main intellectual weapon that I bring is my expertise on novel, non-mainstream quasiclassical techniques that are much faster than quantum-mechanical ones and that allow for significant insights into the physical mechanisms. These techniques are appropriate for ionization processes through long range Coulomb forces. I propose to deliver sophisticated and efficient techniques for tackling some of the most fundamental problems facing Attoscience. My objectives are:1)Explore the correlated dynamics of two-electron escape during the break-up of multi-center molecules triggered by intense and ultra-fast X-ray pulses.2)Explore pump-probe schemes for coherent control and transfer of electrons in multi-center molecules.3)Use infrared laser pulses as an ``attosecond clock" to accurately map the properties of the observed spectra of the final fragments to the temporal evolution of correlated electron escape dynamics during the break-up, by X-rays, of molecules.