Neutron spin-echo spectroscopy

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,... 

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... 

Anticipating further discussions on micro-emulsions, planned for volume V, it is noted that k, or k, or the combination (2kj -i- k ) can also be obtained using scattering techniques or, preferably, combinations thereof. For instance, neutron spin echo spectroscopy (NSES) can be combined with small-angle neutron scattering (SANS) or with dynamic light scattering. Alternatively, 2k + k can be obtained from the polydispersity of the micro-emulsion and then a second type of... 

In this subsection, the theoretical background for SANS and neutron spin-echo measurements carried out with o/w- and w/o-droplet microemulsions will be presented. According to Milner, Safran and others, shape fluctuations in droplet microemulsions can be described in terms of spherical harmonics [42-44]. This offers the possibility to calculate a dynamic structure factor S(q,w) or its Fourier transform, i.e. the intermediate scattering function I(q,t) for the problem, which can be used to analyse dynamical measurements by neutron spin-echo spectroscopy [45]. For the scattering from thin shells I(q,t) was calculated [43]... 

Figure 2.13 Schematic elastic scattering curve of a spherical colloid (e.g. a microemulsion droplet) in solution. As a rule of thumb q 1 is an approximate measure for the spatial resolution of the used scattering experiment. At low values of q (i.e. in the Cuinier region of the scattering curve) the overall size and shape of the particles as well as correlations between different particles can be monitored (typically by static and dynamic light scattering). At high values q, the internal structure of the particles, i.e. the local structure of the interfacial film is resolved (e.g. by neutron or X-ray small angle scattering and neutron spin-echo spectroscopy (NSE)).

Hellweg, Th. and Langevin, D. (1998) Bending elasticity of the surfactant film in droplet microemulsions Determination by a combination of dynamic light scattering and neutron spin-echo spectroscopy. Phys. Rev. E, 57, 6825-6834. 

Huang, J.S..Milner, S.T., Farago, B. and Richter, D. (1987) Study of dynamics of microemulsion droplets by neutron spin-echo spectroscopy. Phys. Rev. Lett., 59, 2600-2603. 

Hayter, J.B. (1981) Quasielastic neutron spin-echo spectroscopy. In S.-H. Chen, B. Chu and R. Nossal. (eds), Scattering Techniques Applied To Supramolecular and Nonequilibrium Systems. Plenum, New York, pp. 3-33. 

Mezei, F., Pappas, C. and Gutberlet, T. (eds) (2003) Neutron Spin Echo Spectroscopy, 1st edn. Vol. 601 Lecture Notes in Physics. Springer, Heidelberg. 

Bu Z, Biehl R, Monkenbusch M, Richter D, Callaway DIE Coupled protein domain motion in Taq polymerase revealed by neutron spin-echo spectroscopy. Proc. Natl. Acad. Set U. S. A. 2005,102 17646-17651. 

Information about the elasticity can be obtained using a variety of scattering methods. Small-angle scattering is mainly used for systems with small interlamellar spacing [75,77-82], whereas light scattering can be applied for the study of swollen systems [76,83,84]. Neutron spin-echo spectroscopy has also been used to directly measure the bilayer dynamics in lamellar liquid crystalline phases [85-87]. 

Neutron Spin Echo Spectroscopy at the NIST Center for Neutron Research... 

---