Correlation functions optical anisotropy

Though derived for DNA, and nucleosome core particles, these twisting correlation functions are potentially useful for the analysis of other filamentous biopolymers. Such analyses of optical anisotropy data for actin filaments... 

This has been explained through the fact that the scattering amplitude is proportional to the optical anisotropy correlation function, a quantity which the breaking of a hydrogen bond modulates in time, a process that affects the optical anisotropy of water. We see, therefore, that the linewidth is the inverse of the average lifetime of the hydrogen bond. 

In the general case, light scattering in matter is caused not only by density fluctuations but also by anisotropy fluctuations and fluctuations of the optical axis orientation of anisotropic areas. Such fluctuations arise as a result of mutual orientation of anisotropic molecules, or of their aggregates, or owing to the internal stresses in solid matter. In this case, the polarizability of scattering elements is represented by a polarizability tensor and two correlation functions (density correlation auid orientation correlation) are introduced (Goldstein and Michalik, 1955 van Aartsen, 1972). 

Four calculations have been reported in related areas of molecule-field interactions. Evans (1982) has simulated the bulk anisotropy for a collection of molecules, which while dipolar were not polarizable nor based on the properties of a real molecule. The field-induced force was not explicitly defined in terms of a dipole-field interaction, rather a full Lennard-Jones potential was used. Coffey has examined the inertial relaxation of dipolar molecules in intense fields (Coffey et al., 1983). Madden has focused on interaction-induced effects in dielectric absorption (Tildesley and Madden, 1983) and transient nonlinear optical measurements in CS2 (Madden, 1987). Samios and Dorfmuller used a similar local field formalism to ours when they examined far IR absorption and utilized equilibrium fluctations to obtain correlation functions for liquid CS2 (Gburski et al., 1987). More details on these calculations... 

In studying the intense laser interactions with the CS2 molecules, and observing the behaviour of the orientational distribution and pair correlation functions [g(S)J through the time-evolution of the optical field-induced anisotropy, we are emphasizing external field-induced phenomena rather than interaction-induced or collision-induced events. 

More recently, the problem of film anisotropy has been treated again in a more thorough fashion by Plieth. " He pointed out that the more fundamental parameter for describing the film optical response normal to the surface is rather than proper, because of the close correlation between the normal component of the electric field vector and the so-called loss function, Im... 

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