Abstract.
Diffusion in anisotropic samples is often studied by quasi-elastic neutron scattering at time-of-flight (t-o-f) instruments. During the data analysis the measured dynamic structure factor S(Q,E) is fitted by a model function, which - reflecting the anisotropy of the sample - depends on the sample orientation. The error introduced in this way will be discussed. Correct measurements can be performed for such cases at a triple axis spectrometer, where energy scan can be performed for a certain Q vector fixed to the sample orientation. Clays show 2D anisotropy in the structure, which is supposed to be visible also in the diffusion of water located between the clay sheets. A first experiment performed on TASP (SINQ) will be shown.
Similar content being viewed by others
References
R.E. Lechner, Solid State Ionics 77, 280–286 (1995)
I. Rosciszewski, Acta Phys. Polonica A 41, 549 (1972)
A.J. Dianoux, F. Volino, H. Hervet, Mol. Phys. 30, 1181–1194 (1975)
M. Bée, Quasielastic Neutron Scattering (Adam Hilger, Bristol and Philadelphia, 1988)
M. Gay-Duchosal, D. Hugh Powell, R.E. Lechner, B. Rufflé, Physica B 276–278, 234–235 (2000)
J. Swenson, R. Bergman, S. Longeville, W.S. Howells, Physica B 301, 28–34 (2001)
R. Dähn et al., Geochim. Cosmochim. Acta 66/13, 2335–2347 (2002)
F. Semadeni, B. Roessli, P. Bni, Physica B 297, 152 (2001)
W.E. Fischer, Physica B 234–236, 1202–1208 (1997)
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Jurányi, F., González, F. & Gvasaliya, S. Geometrical aspects of QENS experiments in case of anisotropic samples. Eur. Phys. J. Spec. Top. 141, 285–288 (2007). https://doi.org/10.1140/epjst/e2007-00055-5
Issue Date:
DOI: https://doi.org/10.1140/epjst/e2007-00055-5