Electron magnetic resonance spectroscopy

L. H. Sutcliffe, The design of spin probes for electron magnetic resonance spectroscopy and imaging, Phys. Med. Biol., 43 (1998) 1987-1993. 

Abstract We overview the application of the electron magnetic resonance spectroscopy... 

Several experiments have been carried out to confirm the physical properties of solitons in mns-polyacetylene [27]. Lately, this excitation has also been studied in another degenerate ground state conjugate polymer, poly(l,6-heptadiene) [28]. The onedimensional spin diffusion and associated spin dynamics are verified from electron magnetic resonance spectroscopy, nuclear magnetic resonance (NMR) spectroscopy and electron nuclear double resonance (ENDOR) measurements [13]. The density of neutral solitons has been estimated by Motsovoy and co-workers [29]. For more details on the physical properties of solitons, the reader is referred to a review article by Heeger and co-workers [13]. However, more theoretical and experimental work is... 

The dielectric permittivity as a function of frequency may show resonance behavior in the case of gas molecules as studied in microwave spectroscopy (25) or more likely relaxation phenomena in soUds associated with the dissipative processes of polarization of molecules, be they nonpolar, dipolar, etc. There are exceptional circumstances of ferromagnetic resonance, electron magnetic resonance, or nmr. In most microwave treatments, the power dissipation or absorption process is described phenomenologically by equation 5, whatever the detailed molecular processes. 

A detailed account is given in Reference 20. The techniques giving the most detailed 3-D stmctural information are x-ray and neutron diffraction, electron diffraction and microscopy (qv), and nuclear magnetic resonance spectroscopy (nmr) (see Analytical methods Magnetic spin resonance X-ray technology). 

Boron s electron deficiency does not permit conventional two-electron bonds. Boron can form multicenter bonds. Thus the boron hydrides have stmctures quite unlike hydrocarbons. The B nucleus, which has a spin of 3/2, which has been employed in boron nuclear magnetic resonance spectroscopy. 

Nuclear magnetic resonance spectroscopy of the solutes in clathrates and low temperature specific heat measurements are thought to be particularly promising methods for providing more detailed information on the rotational freedom of the solute molecules and their interaction with the host lattice. The absence of electron paramagnetic resonance of the oxygen molecule in a hydroquinone clathrate has already been explained on the basis of weak orientational effects by Meyer, O Brien, and van Vleck.18... 

Unpaired electrons and magnetism - One of the consequences of the open (incompletely filled) d" configuration of transition-metal ions may be the presence of one or more unpaired electrons. Such compounds could be described as radicals, and they are detected by techniques such as electron spin resonance spectroscopy. 

I. N. Levine (1975) Molecular Spectroscopy (John Wiley Sons, New York). A survey of the theory of rotational, vibrational, and electronic spectroscopy of diatomic and polyatomic molecules and of nuclear magnetic resonance spectroscopy. 

Bramley, R. and Strach, S.J. 1983. Electron paramagnetic resonance spectroscopy at zero magnetic field. Chemical Reviews 83 49-82. 

Venable, J.H. 1967. Electron paramagnetic resonance spectroscopy of protein single crystals II. Computational methods. In Magnetic Resonance in Biological Systems, eds. A. Ehrenberg, B.G. Malmstrom and T. Vanngard Elmsford. New York Pergamon Press, 373-381. 

There are two major experimental techniques that can be used to analyze hydrogen bonding in noncrystalline polymer systems. The first is based on thermodynamic measurements which can be related to molecular properties by using statistical mechanics. The second, and much more powerful, way to elucidate the presence and nature of hydrogen bonds in amorphous polymers is by using spectroscopy (Coleman et al., 1991). From the present repertoire of spectroscopic techniques which includes IR, Raman, electronic absorption, fluorescence, and magnetic resonance spectroscopy, the IR is by far the most sensitive to the presence of hydrogen bonds (Coleman et al., 1991). 

The techniques available to achieve molecular structure determinations are limited. They include structural analysis with diffraction techniques—such as electron, neutron, and x-ray diffraction—and various absorption and emission techniques of electromagnetic radiation—such as microwave spectroscopy and nuclear magnetic resonance (NMR). For molecules with unpaired spins a companion technique of electron spin resonance spectroscopy (ESR) is highly informative. 

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