Light scattering Polarization effects

Polarization effects are another feature of Raman spectroscopy that improves the assignment of bands and enables the determination of molecular orientation. Analysis of the polarized and non-polarized bands of isotropic phases enables determination of the symmetry of the respective vibrations. For aligned molecules in crystals or at surfaces it is possible to measure the dependence of up to six independent Raman spectra on the polarization and direction of propagation of incident and scattered light relative to the molecular or crystal axes. 

In order to study the mobility of elements of crosslinked structure of CP, it is suitable to use their microdisperse forms [30-35]. On the one hand, in potentiome-tric titration the equilibrium is quickly attained for these forms and on the other hand the effect of light scattering in spectral methods of investigation (e.g., polarized luminescence) can be greatly decreased. 

We have shown in this paper the relationships between the fundamental electrical parameters, such as the dipole moment, polarizability and hyperpolarizability, and the conformations of flexible polymers which are manifested in a number of their electrooptic and dielectric properties. These include the Kerr effect, dielectric polarization and saturation, electric field induced light scattering and second harmonic generation. Our experimental and theoretical studies of the Kerr effect show that it is very useful for the characterization of polymer microstructure. Our theoretical studies of the NLDE, EFLS and EFSHG also show that these effects are potentially useful, but there are very few experimental results reported in the literature with which to test the calculations. More experimental studies are needed to further our understanding of the nonlinear electrooptic and dielectric properties of flexible polymers. 

Size analyses of (using light scatter) some spherical micelles of SDS have indeed shown that the radius of the micelle is almost the same as the length of the SDS molecule. However, if the solute interferes with the outer polar part of the micelle, then the micelle system may change in such a way that the CMC and other properties change. This is observed in the case of the addition of dodecanol to SDS solutions. However, very small additions of solutes show very little effect on CMC. The data in Figure 3.18 show the change in the solubility of naphthalene in SDS aqueous solutions. 

Bickel, W. S., J. F. Davidson, D. R. Huffman, and R. Kilkson, 1976. Application of polarization effects in light scattering a new biophysical tool, Proc. Natl. Acad. Sci. USA, 73, 486-490. Bilbro, J. W., 1980. Atmospheric laser Doppler velocimetry an overview, Opt. Eng., 19, 533-542. Blanchard, D. C., 1967. From Raindrops to Volcanoes Adventure with Sea Surface Meteorology, Doubleday, New York. 

Kilkson, R., W. S. Bickel, W. S. Jetter, and M. E. Stafford, 1979. Influence of absorption on polarization effects in light scattering from human red blood cells, Biochim. Biophys. Acta, 584, 175-179. 

This behavior is not observed uniquely when the angle between the two beams is 90° rather, the intensity of the reflected beam varies continuously with the angle. At 90°, however, the polarization effect is most pronounced. We shall see that some scattering phenomena also show an angular dependence, as well as the fact that scattered light displays maximum polarization at 90°. 

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