Multimodal time-resolved impulsive vibrational spectroscopies

Datum

11.10.2017

Zeit

16:30 - 17:30

Sprecher

Tiago Buckup

Zugehörigkeit

Universität Heidelberg

Sprache

en

Hauptthema

Physik

Andere Themen

Physik

Beschreibung

Impulsive vibrational spectroscopy (IVS) techniques like pump-DFWM (degenerate four wave mixing) and pump-IVS has been developed and exploited to elucidate the interplay of structural changes and energy transport in natural and artificial photosystems based on biopolyenes like carotenoids (e.g. in bacterial light-harvesting complexes, synthetic carotenoid based dyads) and retinoids (e.g. bacteriorhodopsin, Schiff-bases, etc.). Pump-DFWM and pump-IVS are coherent multidimensional time-resolved methods which are able to resolve the dynamics of molecular vibrations from 0 to over 3000cm-1 in electronically excited states with a time resolution better than 20 fs. The application of these techniques allowed, for example, to pinpoint the active molecular vibration modes in the excited state and their excitation mechanism (optically or via ultrafast relaxation from Franck-Condon active modes) in retinal based systems. A very recent progress of my research focus in this field is the development of resonant 2D Raman spectroscopy. 2D Raman with electronically resonant pulses is sensitive to optically active vibrational modes and their vibronic coupling. Therefore, it is an ideal technique to follow in time how chromophores interact with their environment, in particular how specific vibrational modes couple to other degrees-of-freedom.

Letztmalig verändert: 11.10.2017, 09:54:54