Object scattering phenomenon

Chiral objects absorb left and right circularly polarized light to slightly different extents. Tltis phenomenon of circular dichroism [1] became the basis of the most widespread practical chiroptical method in the past few decades. There are some other chiroptical methods based on the interaction of chiral matter with circularly polarized light Optical rotatory dispersion is based on the analogous difference in refraction. Raman optical activity measures differences in scattered light, and circularly polarized luminescence deals with the difference in emission. 

Diffraction is an interference phenomenon occurring when waves are scattered by objects in different positions. Electron diffraction depends on the wave-like properties of electrons and can be used in various ways. One application in inorganic chemistry is the determination of bond lengths and angles of molecules in the gas phase. Its scope is limited as only volatile substances may be studied, and a full interpretation is only possible for molecules containing rather few atoms. 

The phenomenon of electromagnetic scattering and absorption is exploited widely in remote-sensing and laboratory characterization of various objects... 

To illustrate the diffraction phenomenon in one dimension, consider a linear array of identical scattering objects separated by a distance, a. The sum over the atoms in equation 4.41... 

The interesting phenomenon where a mixture of two poor solvents or nonsolvents for a polymer provides a medium that acts as a good solvent for die polymers has been the objective of many studies, by light scattering, " viscometry, " sorption equilibrium, and fluorescence. From these techniques, it has been possible to appreciate how the second virial coefficient Aj and the intrinsic viscosity [11] preferential adsorption coefficient A, and excimer and monomer emission ratio Ie/Im are involved by changing solvent composition. They present ([T)], A2) a maximum or a variation at a certain solvent composition where the polymer behaves as through it were dissolved in a good solvent. 

Color, however, is a very complex phenomenon. Objects can modify light not only by reflectance and selective absorption, as we have seen, but also by transmission, scattering, dispersion, interference, etc.—sometimes all at once. It is the combination of all these possible interactions which ultimately determine the appearance of an object. 

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