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Time-resolved x-ray absorption fine structure (XAFS) spectroscopy with picosecond temporal resolution is a new method to observe electronic and geometric structures of short-lived reaction intermediates. It combines an intense femtosecond laser source sync ...
Spie-Int Soc Optical Engineering, Po Box 10, Bellingham, Wa 98227-0010 Usa2007
The authors report a femtosecond pump-probe study of photochem. of concd. aq. solns. of [Ru(bpy)3]2+, as a function of pump power (up to 2 TW/cm2) at 400 nm excitation. The transient absorption spectra in the 345-660 nm range up to 1 ns time delay enable t ...
Femtosecond pump pulses are strongly attenuated in lithium niobate owing to two-photon absorption; the relevant nonlinear coefficient beta(p) ranges from similar to 3.5 cm/GW for lambda(p) = 388 nm to similar to 0.1 cm/GW for 514 nm. In collinear pump-prob ...
Electronic structure changes are at the origin of the making, breaking and transformation of bonds. These changes can be visualized by measuring the geometric structure in "real-time" during the course of a chemical reaction, a biological function or a phy ...
The environment is important for the exact course of a chemical reaction. As an example of the strong influence of the environment on the reaction, this work studies the isomerization reaction of the chromophore retinal in the binding pocket of the protein ...
The propagation of high-power femtosecond light pulses in lithium niobate crystals (LiNbO3) is investigated experimentally and theoretically in collinear pump-probe transmission experiments. It is found within a wide intensity range that a strong decrease ...
We present a review of wave packet dynamics in different systems and stress their relation to information on the ultrafast structural changes. We show how dynamical information is obtained from ultrafast optical pump-probe studies on structural changes in ...
We describe an experimental setup, which measures transient chemical changes of photoexcited solutes in disordered systems via time-resolved X-ray Absorption Spectroscopy (XAS) with picosecond temporal resolution. The setup combines a femtosecond amplified ...
Ultrafast infrared transient absorption spectroscopy is used to study the photoinduced bimolecular electron transfer reaction between perylene in the first singlet excited state and 1,4-dicyanobenzene in acetonitrile and dichloromethane. Following vibratio ...
Ultrafast spectroscopy was used to study the relaxation processes of charge carriers in ZnO nanocryst. thin films. A broad red-IR absorption band linked to shallowly trapped electrons was obsd. by spectroelectrochem. measurements. Femtosecond transient abs ...
