Nuclear magnetic resonance topicity analysis

This volume of the Handbook illustrates the rich variety of topics covered by rare earth science. Three chapters are devoted to the description of solid state compounds skutteru-dites (Chapter 211), rare earth-antimony systems (Chapter 212), and rare earth-manganese perovskites (Chapter 214). Two other reviews deal with solid state properties one contribution includes information on existing thermodynamic data of lanthanide trihalides (Chapter 213) while the other one describes optical properties of rare earth compounds under pressure (Chapter 217). Finally, two chapters focus on solution chemistry. The state of the art in unraveling solution structure of lanthanide-containing coordination compounds by paramagnetic nuclear magnetic resonance is outlined in Chapter 215. The potential of time-resolved, laser-induced emission spectroscopy for the analysis of lanthanide and actinide solutions is presented and critically discussed in Chapter 216. 

We discuss briefly some basic topics in materials physics such as crystallography, lattice vibrations, band structure, x-ray diffraction, dielectric relaxation, nuclear magnetic resonance and Mossbauer effects in this chapter. These topics are an important part of the core of this book. Therefore, an initial analysis of these topics is useful, especially for those readers who do not have a solid background in materials physics, to understand some of the different problems that are examined later in the rest of the book. 

In this chapter the topic is the techniques for preparing pharmaceutical samples for analysis. Sample preparation of pharmaceutical products as well as biological samples is discussed. The scope of this chapter includes only sample preparation for chromatographic analysis in which the chromatographic system, not the sample preparation, achieves the ultimate isolation of the analyte. Isolation and purification of relatively pure substances for spectral analysis, e.g., infrared spectroscopy, nuclear magnetic resonance, and mass spectrometry, will be discussed elsewhere. This chapter is organized into three groups of discussions. 

Nuclear Magnetic Resonance Spectroscopy.—As noted above, conformational analysis of bicyclo[3.3.1]nonanes is still a topic of considerable interest. A variable-temperature n.m.r. analysis now provides the first case in which the boat-chair-chair-boat equilibrium is directly observed in the amines (17) and (18). In a related case, re-examination of the acetal (19) suggests that the preferred conformation involves a chair carbocyclic ring and a boat heterocyclic ring. This conclusion was made by n.m.r. analysis, using lanthanide shift reagents, by a study of nuclear Overhauser effects, and by measurement of relaxation times of protons. Details have been reported for other 3-azabicyclo[3.3.1]nonanes, and the non-additivity of substituent effects on chemical shifts in 9-thiabicyclo[3.3.1]non-2-enes has been analysed. Both and n.m.r. data have been reported for a series of 9-borabicyclo[3.3.1]non-anes and their pyridine complexes. 

A glance at the table of contents, in volume 10, will show that some topics merit a large number of articles, a reflection of their importance in current analytical science. Several techniques, for example, mass spectrometry, nuclear magnetic resonance spectroscopy, atomic emission spectrometry, microscopy, the various chromatographic techniques (e.g., gas, liquid and thin-layer), and electrophoresis, merit a series of articles, as do areas such as food and nutritional analysis, forensic sciences, archaeometry, pharmaceutical analysis, sensors, and surface analysis. Each of these collections of articles, written by experts in their fields, provides at least as much up-to-date information on that particular subject as a complete textbook. 

The development of hyphenated techniques for rapid separation of mixtures and spectroscopic analysis of its components is a topic of great interest, particularly when the amount of sample is limited and the need for automatization is high. This is the case for high-pressure liquid chromatography nuclear magnetic resonance-mass spectroscopy (HPLC NMR-MS), which has been shown to be extremely useful in certain pharmaceutical and medical applications. 

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