Multinuclear Fourier transform

The objective of this study is to characterize tin-containing polymers on a molecular level by means of high field, high resolution, multinuclear Fourier Transform Nuclear Magnetic Resonance (FT-NMR) (4 ). This study is generally an applied approach dealing with composition and configuration of specific formulations of the copolymer. 

A Multinuclear Fourier Transform NMR Study of Perfluorosulfonate Ionomers... 

It was established in the 1970s that XeF2 in solution was a valuable means of introducing fluorine oxidatively into transition carbonyl compounds to produce carbonyl fluorides (216, 217). Recently, there has been renewed activity in this area, supported by the improvements in multinuclear Fourier-Transform NMR techniques. Among... 

J. W. Akitt NMR and Chemistry An Introduction to the Multinuclear Fourier Transform Era, 3rd ed.. Chapman Hall. London 1992. 

The early NMR studies of molecules sorbed on zeolites used H and 19F resonances. Truly multinuclear work involving 13C, 1SN, and 129Xe in particular began in the early 1970s with the advent of modern Fourier transform spectrometers. 

Recent fundamental books are Akitt s on Fourier transform and multinuclear NMR (156). Mehring s on high-resolution NMR in solids (157), and Levy s on methods and applications (158). Books directed more toward polymers are by Kaufman (159). Bovey (160, 161), and Iven (162). which contains useful reviews. 

Akitt, J. W. "NMR and Chemistry-An Introduction to the Fourier Transform-Multinuclear Era," 2nd ed. Chapman and Hall New York, 1983. 

These early measurements stimulated my interest in NMR spectroscopy, and, on moving to the University of Kent at Canterbury (1972), we were lucky to be able to buy the first Fourier Transform NMR spectrometer in the UK. This instrument was still based on an electromagnet ( H, 100 MHz) but allowed faster acquisition of NMR spectra and enabled the development of multinuclear NMR spectroscopy. This permitted me to start collaborating with Paolo Chini who had taken up an appointment at the University of Milan where he was developing metal carbonyl cluster chemistry. In Milan, Chini had access only to an IR spectrometer that aided the clean preparation and subsequent crystallisation of clusters, and, importantly, an X-ray diffractometer for their structural characterisation. 

A wide range of proton and carbon NMR techniques, almost exclusively using Fourier Transform (FT) spectroscopy, are presented in applications to support proposed chemical structures, with multinuclear NMR being used where appropriate. Polarisation transfer experiments (e.g. DEPT) are used to indicate carbon multiplicity and the use of two-dimensional techniques, which facilitate signal assignment, is seen more frequently in applications. Typical techniques include H- H correlation (COSY and related phase-sensitive experiments) proton-carbon heteronuclear correlation (including inverse... 

Phosphorus-31 NMR spectroscopy has emerged as the most reliable analytic method for stmctural determination of organophosphoras compounds and it has been in use since the development of multinuclear high-field Fourier-transform instmments in the late 1970 s. Phosphoras-31 NMR ( P NMR) is not only used in the structural determination of the organophosphoras confounds but also has been in use in biological and industrial fields. 

Phosphorus occurs predominantly as the isotope which has a nuclear spin value of 1/2 and is therefore visible in nuclear magnetic resonance (NMR) spectrometry. Phosphorus NMR ( P NMR) has been in use since the development of multinuclear, high-field Fourier-transform instruments in the late 1970s. The P NMR method is widely used, with both onedimensional (ID) and multidimensional techniques, in such diverse areas as the characterization of organic and inorganic molecular structures, the analysis of biological fluids, the determination of intracellular pH, the noninvasive study of intact tissues and organs, and quantitative assays of industrial... 

Figure 2 Background signal (2) in the NMR spectrum of a multinuclear probe head. (A) ai NMR spectrum of a 0.1 M solution of [Et2AIO(CH2)2NEt2]2- (B) Spectrum obtained with the test-tube filled with solvent only. For resolution enhancement, the same Lorentz-Gauss transformation was used in both cases before Fourier transformation. Reprinted with permission of Wiley-VCH from Benn R and Rufinska A (1986) Angewandte Chemie, International Edition in English 25 861-881.

J. W. Akitt and R. H. Duncan, Multinuclear study of aluminium isopropoxide - Fourier Transform NMR of a quadrupolar nucleus, J. Magn. Reson. 15, 162-165 (1974). 

Martin, M L, Delpuech, J -J, Martin, G J Practical NMR Spectroscopy, Hey den London, 1980 Shaw, D Fourier Transform NMR Spectroscopy, 2nd ed, Elsevier Amsterdam, 1984, 304 pp Brevard, C, Granger, P Handbook of High Resolution Multinuclear NMR, Wiley New York, 1981, 229 pp... 

The computer then performs a cross-correlation exercise, depending on the manner of the noise-modulation, before the Fourier transform. This method gives added flexibility and may have applications in multinuclear work. 

---