Markus Kowalewski - Coherent Signatures of Conical Intersections in Ultrafast X-Ray Spectroscopy
Date: Mar 1, 2017
Time: 11:00 - 12:00
Speaker: Markus Kowalewski
University of California, Irvine, USA
Location: CFEL (Bldg. 99)
Room: Seminar Room IV, O1.111
Host: Angel Rubio
The rates and outcomes of virtually all photochemical and photobiological processes are dominated by conical intersections (CIs), which provide a fast sub-100-femtosecond nonradiative pathway back to the ground state. At a CI, the electronic and nuclear degrees of freedom frequencies are comparable and strongly mix due to the breakdown of the Born-Oppenheimer approximation.
A major challenge for their direct detection is
the rapidly varying gap between the electronic surfaces in their vicinity.
Modern XUV/X-ray light sources provide spectral broad and temporal short
pulses, which potentially allow for monitoring CIs directly. We present
theoretical studies on novel spectroscopic methods, which make use of
ultrashort X-Ray laser pulses.
The presented methods include Raman (TRUECARS),
time resolved photo electron spectroscopy and possible signatures of electronic
coherences in time resolved X-Ray diffraction.