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In this chapter, aspects of the planning and optimization of a neutron scattering experiment are covered, including attenuation, multiple scattering, data normalization, counting statistics, resolution, corrections for polarization analysis, and spurions. Practical aspects of diffraction experiments are described, including instrumentation, Rietveld refinement, anisotropic displacement parameters, the Ewald sphere construction, Lorentz factors, extinction and multiple scattering. Practical aspects of spectroscopy are also described, including triple-axis, time-of-flight and backscattering spectrometers, direct and indirect geometry, and some specific points arising in time-of flight inelastic scattering.

Laser desorption mass spectrometry is demonstrated in this chapter as a general tool for the analysis of solid materials, including fullerenes, metals, inorganic compounds, and biomolecules. These experiments use a pulsed Nd:YAG laser coupled with a time-of-flight mass spectrometer. When the laser intensity is low, intact molecules can be desorbed from a surface and ionized, allowing their identification. When the laser intensity is higher, vaporization of material can produce a plasma like that seen in the LIBS experiments, and new atomic clusters can form as their vapor condenses. A digital oscilloscope collects the time-resolved ion signals from either an electron multiplier tube or microchannelplate detector. The derivation of mass assignments from the signal-vs-time data is discussed, as are the factors determining mass resolution and isotopic abundances. Background information is provided about fullerenes, metal atom clusters, and the technique of matrix-assisted laser desorption ionization (MALDI).

This chapter describes the main experimental techniques used to measure the drift velocity in superfluid ⁴He at low temperature. The experimental results are then presented by showing the contributions to the ion drag due to the different elementary excitations of the superfluid. The theoretical description of the processes of ion scattering off phonons, rotons, and ³He atomic impurities is also presented, and the theoretical predictions are compared with experimental results. The use of the formalism of the Boltzmann transport equation to predict how the drag force on an ion in the superfluid is determined by the different scattering mechanisms is discussed.

Metal carbonyls are volatile inorganic complexes with applications in homogeneous catalysis and photolithography. The strong photochemical activity of these systems for ultraviolet light absorption is well known. In this chapter, pulsed UV laser excitation of these complexes is carried out within the ion source of a time-of-flight mass spectrometer. The resulting multiphoton processes produce dissociation and ionization. The experiment demonstrates the application of multiphoton ionization and the rich variety of fragmentation/ionization processes that can be induced. Isotopically resolved mass spectra provide clear illustrations of the natural abundances of metal isotopes.