Annual reports on NMR spectroscopy 

About: Annual reports on NMR spectroscopy is an academic journal published by Elsevier BV. The journal publishes majorly in the area(s): Nuclear magnetic resonance spectroscopy & Chemical shift. It has an ISSN identifier of 0066-4103. Over the lifetime, 409 publications have been published receiving 11505 citations. The journal is also known as: Annual reports on nuclear magnetic resonance spectroscopy.

119Sn-NMR Parameters

Abstract: Publisher Summary Tin (Sn) compounds are well-recognized both in basic research and in industrial applications. Tin NMR spectroscopy includes three magnetically active tin isotopes namely, 115Sn, 117Sn , and l19Sn. However, most tin NMR parameters refer to the 119Sn nucleus owing to its properties such as abundance, magnetic moment, and NMR frequency. This chapter describes: (1) the compilation and updation of 119Sn chemical shifts (δ 119Sn) from studies on organotin compound and inorganic tin compounds, (2) indirect nuclear spin-spin couplings, (3) relaxation mechanisms concerning the 119Sn nucleus, and (4) experimental details for 1I9Sn-NMR measurements. It is observed that with modem equipment there are, in principle, no serious experimental difficulties in observing 119Sn resonances either directly or by heteronuclear double resonance. δ 119Sn data, available for all kinds of tin compounds, significantly allows using this parameter in an empirical way in order to find models for the qualitative interpretation of δ 119Sn. This also applies to couplings involving the l19Sn nucleus, which serve as a sensitive tool in the discussion of structure and bonding. All 119Sn-NMR parameters of tin compounds largely concern measurements in the liquid state.

NMR Spectroscopy of Biofluids

Abstract: Publisher Summary This chapter reviews that the analysis of biofluids provides a unique window into the biochemical status of a living organism since the composition of a given biofluid modulates according to the level of function of the cells that are intimately concerned with its manufacture and secretion. One of the most successful approaches to biofluid analysis has been the application of nuclear magnetic resonance (NMR) spectroscopy and studies can be divided into those that are largely analytical or dynamic in nature. Analytical biofluid NMR studies are concerned primarily with the collection, assignment, and quantization of NMR spectra and their interpretation in biochemical terms. The chapter also explores that the types of dynamic interactions amenable to NMR study includes: enzymatic biotransformations, metal complexation reactions, binding of small molecules to macromolecules, cellular, and micellar compartmentation that occur in different biofluids to varying degrees. All biological fluids have their own characteristic physicochemical properties and these partly dictate the types of NMR experiment that may be employed to maximize the biochemical information from each fluid type. It also reviews that there are also two types of accessible information available in an NMR experiment on a biological fluid. These have been termed latent and patent biochemical information.

Dipolar recoupling under magic-angle spinning conditions

Abstract: Experimental NMR techniques designed to recouple weak homonuclear and heteronuclear dipolar coupling interactions under magic-angle spinning conditions are discussed. Developments and applications of such dipolar recoupling techniques are reviewed, covering the period 1994-early 1999. The various homonuclear and heteronuclear dipolar recoupling pulse sequences are illustrated and explained within the framework of average Hamiltonian theory.

Nitrogen NMR Spectroscopy

Abstract: Publisher Summary Nitrogen nuclear magnetic resonance (NMR) is finding new applications. This chapter presents some of the applications of the nitrogen NMR. The element nitrogen in its natural occurrence has two isotopes; 14N and 15N. The nuclei of both possess magnetic moments; consequently, both give nuclear magnetic resonance (NMR) spectra and additionally may affect the spectra of other nuclei. The NMR spectra of nitrogen nuclei may provide an important contribution to the development of the general theory of chemical shifts, by allowing a rigorous check of current theories. This arises from the variety of nitrogen valence states occurring in the molecules, including more or less non-bonding electron pairs, many types of bonds of varying polarity and hydrogen bonding, as well as the common occurrence of nitrogen atoms in both neutral and ionic species. 14N nucleus has an electric quadrupole moment and this is responsible for producing broad-line NMR spectra. Broad lines often occur both in the spectrum of the 14N nucleus and in the spectrum of any nucleus spin coupled to the nitrogen nucleus that may preclude the detection of any spin-spin coupling between these nuclei. The electric quadrupole relaxation process of the 14N nucleus may influence the NMR spectra of nuclei that are spin-coupled to it. The most frequently encountered example is the N-H coupling. The chapter presents some examples of nitrogen chemical shifts in the organic and inorganic molecules. However, spin-spin coupling, involving nitrogen nuclei, is readily observed for the 15N isotope than for 14N. As 15N nuclei possess a spin of 1/2 and no quadrupole moment, these give NMR spectral patterns similar to those arising from lH and 19F interactions.

Nuclear Magnetic Resonance Spectroscopy of Boron Compounds Containing Two-, Three- and Four-Coordinate Boron

Abstract: Publisher Summary This chapter explores that the influence of boron chemistry on various areas of research in inorganic, organic, and theoretical chemistry is well documented. In fact, many models currently employed to describe chemical bonding in general can be traced to attempts to understand bonding in boranes. The confirmation of many theoretical predictions in boron chemistry relies on direct and indirect structural information provided by various physical methods that fortunately became available almost at the same rate as that with which the interest in boron compounds was growing. It discusses that developments in boron chemistry have been greatly accelerated by nuclear magnetic resonance (NMR). 11 B NMR has been at the centre of interest from the beginning accompanied by routine 1 H NMR measurements: and occasional 14 N, 19 F and 31 P NMR work. The availability of “multinuclear” facilities for PFT NMR spectrometers stimulates the measurement of the NMR spectra of other nuclei, like 29 Si, l19 Sn or other metals, to obtain additional information. The chapter not only summarizes the experimental facts required for obtaining the maximum information from NMR studies on boron compounds but also attempts to incorporate new NMR parameters into the known data set.