Mainz 2017 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
MO: Fachverband Molekülphysik
MO 16: Posters 3: Experimental Techniques and Theoretical Approaches
MO 16.1: Poster
Donnerstag, 9. März 2017, 17:00–19:00, P OG1
Resolving Vibrational from Electronic Coherences in Two-Dimensional Electronic Spectroscopy: The Role of the Laser Spectrum — Franco V. De A. Camargo1, •Lena Grimmelsmann1,2, Harry L. Anderson3, Stephen R. Meech1, and Ismael A. Heisler1 — 1School of Chemistry, Norwich Research Park, University of East Anglia, Norwich NR4 7TJ, United Kingdom — 2Physical Chemistry II, Ruhr-University Bochum, 44780 Bochum, Germany — 3Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, United Kingdom
Light-induced coherent superposition of states are observed through the presence of oscillations in two-dimensional electronic spectroscopy (2DES). The pioneering 2DES studies on coherences mostly focused on single coordinates of the real part of 2D maps, with limited scanning of the waiting time, because of the long data acquisition times. Here we use a state-of-the-art 2D spectrometer that quickly acquires data with very good signal-to-noise to recover complex-valued 2DES maps and study vibrational coherences in a zinc-porphyrin monomer. Further we show that these signatures are critically dependent on the laser spectrum, demonstrating that a blueshift filters pathways so that the final result matches exactly those expected for an electronic coherence. This result is of crucial importance for the interpretation of coherences in 2DES. Finally, we use this new understanding of the laser spectrum effects to perform a complementary 2D experiment that lifts any ambiguity in the interpretation.