Echo spectroscopies

A1.6.4.4 NONLINEAR RESPONSE SYSTEMS COUPLED TO AN ENVIRONMENT (A) ECHO SPECTROSCOPY... 

Figure C3.5.3. Schematic diagram of apparatus used for (a) IR pump-probe or vibrational echo spectroscopy by Payer and co-workers [50] and (b) IR-Raman spectroscopy by Dlott and co-workers [39]. Key OPA = optical parametric amplifier PEL = free-electron laser MOD = high speed optical modulator PMT = photomultiplier OMA = optical multichannel analyser.

D. Richter, Phys. Rev. Lett., 80, 2346 (1998). Chain Motion in an Unentangled Polymer Melt A Critical Test of the Rouse Model by Molecular Dynamics Simulations and Neutron Spin Echo Spectroscopy. 

Keywords Neutron spin echo spectroscopy Polymer dynamics Reptation ... 

The application of neutron spin-echo spectroscopy to the analysis of the slow dynamics of biomolecules is still in its infancy, but developing fast. The few published investigations either pertain to the diffusion of globular proteins in solution [332-334] or focus on the internal subnanosecond dynamics on the length scale, <10 A as measured on wet powders [335,336]. The latter regime overlaps with other quasi-elastic neutron scattering methods as backscattering and TOE spectrometry [337-339]. 

Monkenbusch M (2003) In Mezei F, Pappas C,Gutberlet T (eds) Neutron spin echo spectroscopy. Basics, trends and applications, vol 601. Springer, Berlin Heidelberg New York... 

C, Gutberlet T (eds) Neutron spin echo spectroscopy. Basics, trends and applications,... 

Extensive analysis of the EPR and redox behavior of this unusual copper protein led to the hypothesis that the protein might contain a Cu(A) site similar to that in cytochrome oxidase (Riester et ai, 1989) and that the unusual seven-line EPR is due to the Cu(A)-type site. An alternative interpretation of this EPR is based on electron spin-echo spectroscopy as well, and that is that the seven-line EPR is due to a half-met Cu—Cu pair and to unusual type I sites (Jin et ai, 1989). Three sets of spin-echo peaks can be attributed to nitrogens on imidazole ligands to a CuA-type site and to another imidazole on the half-met site. The electron spin-echo spectra of cytochrome oxidase are similar, although there is not enough copper in cytochrome oxidase for a half-met site. Conceivably, the property of delocalization of the paramagnetic electron could be effected by the proposed bridging between Cub and heme as (nomenclature summarized by Capaldi, 1990), which are proposed to be 3-4 A apart. 

D photon-echo spectroscopy of hydrogen-bond dynamics in liquid water... 

Ranee, M. and Byrd, R.A. 1983. Obtaining high-fidelity spin-1/2 powder spectra in anisotropic media Phase-cycled Hahn Echo spectroscopy. J. Magnetic Resonance 52 221-240. 

Di Benedetto, F., Costagliola, P., Benvenuti, M. et al. (2006) Arsenic incorporation in natural calcite lattice evidence from electron spin echo spectroscopy. Earth and Planetary Science Letters, 246(3-4), 458-65. 

When deciding to study the dynamics of electronic excitation energy transfer in molecular systems by conventional spectroscopic techniques (in contrast to those based on non-linear properties such as photon echo spectroscopy) one has the choice between time-resolved fluorescence and transient absorption. This choice is not inconsequential because the two techniques do not necessarily monitor the same populations. Fluorescence is a very sensitive technique, in the sense that single photons can be detected. In contrast to transient absorption, it monitors solely excited state populations this is the reason for our choice. But, when dealing with DNA components whose quantum yield is as low as 10-4, [3,30] such experiments are far from trivial. 

The relationship between spectroscopic and statistical functions has been exploited for a variety of phenomena related in different ways to the dynamical response of the medium. We cite as examples spectral line broadening, photon echo spectroscopy and phenomena related to TDFSS we are examining here. A variety of methods are used for these studies and we add here methods based on ab initio CS. The basic model is actually the same for all the methods in use ab initio CS has the feature, not yet implemented in other methods, of using a detailed QM description of the solute properties, allowing a description of effects due to specificities of the solute charge distribution. 

Everaers R, Sukumaran SK, Grest GS, Svaneborg C, Sivasubramanian A, Kremer K (2004) Rheology and microscopic topology of entangled polymeric liquids. Science 303 823-826 Ewen B, Richter D (1995) The dynamics of polymer melts as seen by neutron spin echo spectroscopy. Macromol Symp 90 131-149... 

PFGE Pulsed field gradient echo spectroscopy... 

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