Elastic and inelastic neutron scattering

In this paper we discuss how neutron scattering spectroscopy can be applied to the study of the structure and dynamics of adsorbed molecules. Since reviews of elastic and inelastic neutron scattering from adsorbed films have recently appeared (1.-3), our purpose here is not to present a comprehensive survey of every adsorbed system investigated by neutron scattering. Rather, we shall be concerned primarily with two questions which are basic to the characterization of adsorbed species on catalysts and which have been central to the discussion of this symposium. These are the extent to which the neutron scattering technique can be used to determine 1) the orientation and position of an adsorbed molecule and 2) the strength and location of the forces bonding a molecule to a surface. 

A very complete study of the self-dynamics of water close to some well-defined hydrophilic surface as the Vycor surface has been performed by quasi-elastic and inelastic neutron scattering it has been done for levels of hydration ranging from full hydration down to the lowest one (25%), corresponding to one monolayer coverage of water molecules and as a function of temperature [69]. We report here the main results. 

Fu H, Trouw F and Sokol P E (1999), A quasi-elastic and inelastic neutron scattering study of H2 in zeolite , J Low Temp Phys, 116, 149. 

Fischer, E. W. (1978) Studies of structure and dynamics of solid polymers by elastic and inelastic neutron scatterings, Pure Appl. Chem., 50, 1319 1341. 

Fischer EW (1978) Studies of stmcture and dynamics of solid polymers by elastic and inelastic neutron scattering. Pure Appl Chem 50 1319-1341 Flory PJ (1949) Thermodynamics of crystallization in high polymers. IV. A theory of crystalline states and fusion in polymers, copolymers, and their mixtures with diluents. J Chem Phys 17 223-240... 

Given the importance of the photon heating contribution in plutonium burning fast reactor cores, a comprehensive validation work is under way for ECCO/ERANOS. Within this framework, PSI has contributed with both an experimental and an analytical effort. On the experimental side, thermoluminescent detector (TLD) measurements were performed in some of the aforementioned CIRANO configurations. With regard to methods/calculational aspects, an important effort was necessary to produce consistent neutron kerma factors and photon spectra data (from photon production due to radiative neutron capture, fission, and both elastic and inelastic neutron scattering). 

In this review, we have attempted to survey what has been learned so far about lanthanide magnetism from both elastic and inelastic neutron scattering experiments. In a field as vast as this, there have inevitably had to be several omissions. Thus, we have had to omit discussions of critical scattering from lanthanide systems, of the very interesting studies of cooperative Jahn-Teller effects in some rare earth compounds, of measurements of the phonon spectra of these systems, and of a large number of neutron diffraction studies of many rare earth compounds other than those described in section 3.5. 

A detailed investigation, involving elastic and inelastic neutron scattering and Mossbauer spectroscopy has been carried out on Nation membranes as a function of water content. Nafion membranes consist of a perfluoroethylene backbone with side chains having a terminal sulphonic acid group. 

QUASI-ELASTIC AND INELASTIC NEUTRON SCATTERING STUDY OF CuTi AMORPHOUS HYDRIDES... 

Ro-vibronic spectroscopies in the UV-Visible-Infrared and Micro-wave energy range, X ray and electron diffraction, incoherent and coherent elastic and inelastic neutron scattering, Raman scattering. Nuclear Magnetic resonances etc. all contain a vibrational contribution. Other non spectroscopic properties such as the various thermodynamical quantities contain the vibrational contributions. 

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