Observation-time dependent structural information from quasielastic neutron scattering

To obtain structural information from dynamic structure studies is in many cases one of the main objects of quasielastic neutron scattering experiments. The kind of energy-analyzing instrumentation that is required, what type of information is obtained and how this is achieved by varying not only the energy and the momentum transfer vector Q, but also the observation time, is discussed with reference to experiments on several complex systems, such as ionic conductors, molecular crystals, proteins and biological membranes. The connection between observation time and the experimental window of Fourier time is outlined. This discussion demonstrates that both, a large energy range and an extensive variation of the observation time is required to obtain a maximum amount of information on dynamic structure. (C) 2001 Elsevier Science B.V. All rights reserved.