Time-resolved diffraction studies

Time resolved diffraction studies Multiple simultaneous techniques-... 

Time-Resolved Diffraction Studies on Membranes During Active Transport Processes... 

Short pulses of softer X-rays of, for example, 3keV energy are very attractive for time-resolved diffraction studies of complex molecules and solids [9.298], The duration of laser-produced X-rays is much shorter (Ips) than... 

Joe Wong, E. Larson, J. Holt, P. Waide, B, Rupp and R. Frahm, Time-resolved diffraction study of solid combustion reactions. Science, 249, 1406-1409 (1990). 

Harford J and Squire J (1997) Time-resolved diffraction studies of muscle using synchrotron radiation. Reports of Progress in Physics 60 1723-1787. 

An interesting feature of polarized IR spectroscopy is that rapid measurements can be performed while preserving molecular information (in contrast with birefringence) and without the need for a synchrotron source (X-ray diffraction). Time-resolved IRLD studies are almost exclusively realized in transmission because of its compatibility with various types of tensile testing devices. In the simplest implementation, p- and s-polarized spectra are sequentially acquired while the sample is deformed and/or relaxing. The time resolution is generally limited to several seconds per spectrum by the acquisition time of two spectra and by the speed at which the polarizer can be rotated. Siesler et al. have used such a rheo-optical technique to study the dynamics of multiple polymers and copolymers [40]. 

Traditionally, x-ray spectroscopy measures an inhomogeneous distribution of structures, represented by the nuclear Debye Waller factors, and yields no information on the time scales of their rearrangements. Collective protein motions after fast optical triggers, on the other hand, have been studied with the help of pulsed synchrotron radiation with nanosecond time resolution (11). (See also Ref. 12 for a collection of review articles on time-resolved diffraction techniques.)... 

However, there will still be a place for spectroscopic studies, as the diffraction studies will raise many questions, such as why one type of molecule proceeds down a particular path whilst other, related molecules proceed down an entirely different path, yielding different products. Spectroscopic studies, which provide information on the force field in a molecule, may well be able to answer such questions when diffraction and spectroscopic studies, together with theory, are combined. Thus, we can expect three strongly coupled parallel streams of research, i.e. time-resolved diffraction, time-resolved spectroscopy and related theoretical studies, to develop over the next decade. 

Lee, D., Ndieyira, J.W. and Rayment, T. (2002) In situ time-resolved structural study of an electrode process by surface differential diffraction, in Spectroscopic tools for the analysis of electrochemical systems (ed. J. McBreen), Electrochemical Society Proceedings, vol. 99 (15),... 

The purpose of this section is to describe recent achievements in time-resolved X-ray diffraction from liquids. Keeping the scope of the present chapter in mind, neither X-ray diffraction from solids nor X-ray absorption will be discussed. The majority of experiments realized up to now were performed using optical excitation, although some recent attempts using infrared excitation were also reported. The main topics that have been studied are (1) visualization of atomic motions during a chemical reaction, (2) structure of reaction intermediates in a complex reaction sequence, (3) heat propagation in impulsively heated liquids, and (4) chemical hydrodynamics of nanoparticle suspensions. We hope that the actual state-of-the-art will be illustrated in this way. 

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