Nuclear magnetic resonance splitting

NMR Nuclear magnetic resonance [223, 224] Chemical shift of splitting of nuclear spin states in a magnetic field H [225], C [226, 227], N [228], F [229], 2 Xe [230] Other Techniques Chemical state diffusion of adsorbed species... 

Of spectroscopic teclmiques, nuclear magnetic resonance (NMR) has been most widely used to measure orientational ordering in liquid crystals [M, 57 and ]. Most commonly, changes of line splittings in the spectra of... 

Monomer (Section 6 21) The simplest stable molecule from which a particular polymer may be prepared Monosaccharide (Section 25 1) A carbohydrate that cannot be hydrolyzed further to yield a simpler carbohydrate Monosubstituted alkene (Section 5 6) An alkene of the type RCH=CH2 in which there is only one carbon directly bonded to the carbons of the double bond Multiplicity (Section 13 7) The number of peaks into which a signal IS split in nuclear magnetic resonance spectroscopy Signals are described as singlets doublets triplets and so on according to the number of peaks into which they are split... 

Multiplicity (Section 13.7) The number of peaks into which a signal is split in nuclear magnetic resonance spectroscopy. Signals are described as singlets, doublets, triplets, and so on, according to the number of peaks into which they are split. 

Something of scientific interest (among numerous other applications, Pascal s triangle is used to predict nuclear magnetic resonance [NMR] multiplet splitting patterns) has been created from the repeated application of a simple rule. 

Diethylamino)trimethylstannane is a colorless liquid which boils at 36°/6 mm. The compound is quickly hydrolyzed by moisture. The proton nuclear magnetic resonance spectrum of a neat sample shows a CH3—Sn resonance at 9.92 r with HChs—Sn119 splitting of 56.5 cycles and HCh,—Sn117 splitting of 54.0 cycles. The ethyl resonance consists of a triplet at 9.10 r... 

As indicated in the previous discussion, Mossbauer spectroscopy provides information that when coupled with results using other structural techniques assists in determining the structure of the complex under analysis. The relationships between the various techniques are summarized in Table II. The Mossbauer chemical shift provides information about the 4 electron contribution to the bond between the metal and the ligands in a complex. Similar estimates can be obtained from the results of measurements on the fine structure in the x-ray absorption edge and nuclear magnetic resonance data. The number of unpaired electrons can be evaluated from magnetic susceptibility data, electron spin resonance, and the temperature coeflScient of the Mossbauer quadrupole splitting (Pr). 

Roberts, J. D., Introduction to the Analysis of Spin-Spin Splitting in High Resolu tion Nuclear Magnetic Resonance Spectra, W. A. Benjamin, New York, 1061. 

Nuclear magnetic resonance spectra may be so simple as to have only a single absorption peak, but they also can be much more complex than the spectrum of Figure 9-23. However, it is important to recognize that no matter how complex an nmr spectrum appears to be, it involves just three parameters chemical shifts, spin-spin splittings, and kinetic (reaction-rate) processes. We shall have more to say about each of these later. First, let us try to establish the relationship of nmr spectroscopy to some of the other forms of spectroscopy we already have discussed in this chapter. 

Fig. 3.63 First order splitting patterns for aromatic protons. Data reproduced from M. Zanger (1972). The Determination of Aromatic Substitution Patterns by Nuclear Magnetic Resonance , Organic Magnetic Resonance, 4,4. Published by Heyden and Son Ltd.

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