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Polarisability anisotropy, effective

Since polarization effects vanish with 1/R whereas the McConnell equation (2) contains l/R, it is obvious that polarisation effects can be observed when magnetic anisotropy effects are far beyond 0.1 ppm, hence polarizations should not be neglected when using the McConnell equation for isotropic chemical shifts. [Pg.67]

Anisotropy in polymer solutions is rather rare, but, where it occurs, the effect on the derived molecular weight can be large enough to warrant appropriate corrections. The procedures have been developed by Utiyama124) and by Utiyama and Kurata125). Without a polariser or analyser the normal reciprocal scattering function Kc/Rtf can be measured. It is denoted by Z(0) the form of which contains an anisotropy parameter 5 which is a function of the number of optically anisotropic elements and the principal polarisabilities in the chain ... [Pg.195]

From the simulations, we conclude that two hydrogen bonding force constants are a basic requirement for reproducing the measured spectrum. If a water-water potential generates sufficiently large force constant differences for the different proton configurations (or the different relative dipole-dipole orientations in water or ice), it should produce the same effect as seen in the LR model. The anisotropic properties of the classic potentials are a result of charge interaction and this anisotropy should increase in the polarisable potentials and hence they produce a broad optic peak. This broad peak indicates that the orientational variation of the potential function has been increased considerably but it may still be less than the critical value of 1.5 as we indicated in the section 6.1. One would, therefore, expect that a better polarisable potential would, eventually, be able to reproduce the split optic peaks in the measured INS spectrum. [Pg.529]

Magnetic field orientation is analogous to the induced-polarisation effect for electric-field orientation. Here it is the anisotropy of the magnetic susceptibility of the molecule that leads to a lowest interaction energy for a particular orientation of the molecule in the field. [Pg.383]

The effect of anisotropy may be best seen by examining the polarised components of scattering. In this context, vertical polarisation (designated by V) refers to polarisation of the electric vector in a plane perpendicular to that containing the incident and the scattered ray, whereas horizontal polarisation refers to polarisation perpendicular to this plane. [Pg.96]

In the presence of redox couples confined to the hydrophobic liquid phase, photoinduced heterogeneous electron transfer can be effectively monitored by photoelectrochemical techniques under potentiostatic conditions. The photocurrent responses are uniquely related to specifically adsorbed porphyrins, as demonstrated by the photocurrent anisotropy to the angle of polarisation of the incident illumination (Section 4.3). Systematic studies of the photocurrent intensity as a function of the formal potential of the redox couple and the Galvani potential difference revealed that the dynamics of electron transfer are determined by the distance separating the redox species at the interface. Other processes including decay of the electronically excited state, back electron transfer, porphyrin regeneration and coupled ion transfer play important role on the dynamics of the photocurrent responses. [Pg.566]

A last point should not be forget in the comparison of dielectric and electrooptic measurements of the polarisability. The latter one measures in fact the anisotropy of polarisability (Xy — We have considered our result as giving ay and compared it to theories which neglect any transversal displacement of the counter-ions. While this is reasonable it doesn t means that transversal movements or end effects do not play a role in the value of the dielectric constant and its dispersion. [Pg.283]


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See also in sourсe #XX -- [ Pg.456 , Pg.550 ]




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Anisotropy effects

Polarisability

Polarisability anisotropy

Polarisability effective

Polarisable

Polarisation

Polarisation effect

Polariser

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