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Neutron scattering in molecular liquids: Influence of orientational degrees of freedom and the prepeak in a fragile glass former

Christoph Theis·Rolf Schilling
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Abstract

The intermediate scattering function S(q,t) for neutron scattering is expanded with respect to a complete set of correlation functions which describe the dynamical correlations in a molecular liquid. For the static ns-structure factor S(q) of a system of diatomic molecules the results of the expansion are compared with the exact results from a MD-imulation and it is shown that the Sears-expansion, which is commonly used to interpret such data, fails in the supercooled regime. The representation for S(q) is used to draw conclusions about the q-dependence and especially the origin of the prepeak.

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Christoph Theis, Rolf Schilling. 1998-08-07. Neutron scattering in molecular liquids: Influence of orientational degrees of freedom and the prepeak in a fragile glass former. https://arxiv.org/abs/cond-mat/9808074

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