Effect, diamagnetic

The reported Meissner fraction was an important property to follow during the early days of superconductivity research. The magnitude of this diamagnetic effect, when properly measured, gives a good indication of the homogeneous nature of the materials being prepared in different laboratories. The first reported values were low, 2 to 15%, but as the composition, structure, and synthetic conditions became better known, the values increased to 70-80%— indicative of bulk superconductivity in an essentially pure product. 

All peaks are shifted toward higher fields because of the diamagnetic effect of the solubilized benzene. 

Criticize or defend the following proposition The more carbon atoms there are in the alcohols, the more hydrophobic these compounds become and the more enriched the micelles become relative to the aqueous phase the magnitude of the chemical shift increases as the extent of solubiliation in the micelles increases owing to the diamagnetic effect of the phenyl groups. 

In these equations gi is the orbital g-factor corrected for quantum electrodynamic, relativistic and diamagnetic effects [11]. A gi is a small correction to the orbital g factor arising from non-adiabatic mixing of excited electronic states, whilst g v and ger are the nuclear and electronic contributions to the rotational g-factor, gr. 

Figure 3-4 illustrates how the diamagnetic effect of benzene is shielding (+) above and below the ring, but deshielding (—) around the edge. This effect was modeled quantitatively by McConnell as the influence of a magnetic dipole on the point in space at which a proton resides. He derived the formula... 

If the bulk diamagnetic effects of an organic liquid are ignored (Bothner-By and Naar-Colin, 1958) and the magnetic field at a... 

This is only strictly true if one neglects diamagnetic effects, which are quadratic in the magnetic field strength, a consideration which can become important for high Rydberg members (see chapter 10). 

DFT [95] was generalized to include relativistic effects by MacDonald and Vosko [96] and by Ramana and Rajagopal.[97] By omitting small diamagnetic effects one-electron equations were obtained that contained a scalar effective potential as well as an effective magnetic field caused by the polarization. In cases where the paramagnetic currents cannot be neglected, it is necessary to resort to a current-density formalism.[98,99]... 

Labarre and co-workers154 166 and another group156 have subsequently reported that criterion (c) is invalid and this has been withdrawn. It was shown that the concentration dependence of the molar magnetic rotation of an aromatic molecule does not correlate with diamagnetic effects of an induced ring current, but rather it is associated with the concentration-dependent change of the internal field of the solute. Consequently it does not reflect the aromaticity of the compound. 

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