Real-time dynamics of electronic excitations in molecules: phenomena and mechanisms

• Applicant: Professor Dr. Lorenz S. Cederbaum
• Subject Area: Theoretical Chemistry: Electronic Structure, Dynamics, Simulation
• Term: from 2011 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 191334972

• Final Report Year: 2015

Final Report Abstract

In this project we opened up the new field of charge migration and separation processes triggered by excitation of molecular systems. Several different molecules of immediate experimental interests have been studied and different aspects of the phenomenon have been elucidated. Important factors influencing charge separation relevant for the creation of chemical potential have been accurately characterized. Tracing ultrafast electronic relaxation processes is possible by employing attosecond pulses in a pump probe fashion. Required theoretical foundations for describing this technique have been established where the theoretical methodology and corresponding implementations developed within the project helped us to outline the design of corresponding experiments. The detailed understanding of the electron density evolution in time makes it possible to predetermine the follow-up nuclear reaction pathways and thus the molecular reactivity upon excitations. We hope that the present research will stimulate future experimental and theoretical studies.

Publications

• Tracing molecular electronic excitation dynamics in real time and space, J. Chem. Phys. 123, 144302 (2010)
  A. D. Dutoi, L. S. Cederbaum, M. Wormit, J. H. Starcke and A. Dreuw
  
• An Excited Electron Avoiding a Positive Charge, J. Phys. Chem. Lett. 2, 2300 (2011)
  A. D. Dutoi and L. S. Cederbaum
  
• Ultrafast charge separation driven by differential particle and hole mobilities, J. Chem. Phys. 134, 024303 (2011)
  A. D. Dutoi, M. Wormit and L. S. Cederbaum
  
• Time-resolved Pump-Probe Spectroscopy to Follow Valence Electronic Motion in Molecules: Theory, Phys. Rev. A 88, 013419 (2013)
  A. D. Dutoi, K. Gokhberg and L. S. Cederbaum
  (See online at https://doi.org/10.1103/PhysRevA.88.013419)
• Time-resolved pump-probe spectroscopy to follow valence electronic motion in molecules: Application, Phys. Rev. A 90, 023414 (2014)
  A. D. Dutoi and L. S. Cederbaum
  (See online at https://doi.org/10.1103/PhysRevA.90.023414)
• What will it take to observe processes in ’real time’?, Nature Photonics 8, 162 (2014)
  S. R. Leone, C. W. McCurdy, J. Burgdorfer, L. S. Cederbaum, Z. Chang, N. Dudovich, J. Feist, C. H. Greene, M. Ivanov, R. Kienberger, U. Keller, M. F. Kling, Z.-H. Loh, T. Pfeifer, A. N. Pfeiffer, R. Santra, K. Schafer, A. Stolow, U. Thumm and M. J. J. Vrakking
  (See online at https://doi.org/10.1038/nphoton.2014.48)