Theory of Light Scattering by an Isotropic System Composed of Anisotropic Units. Out-of-Plane Scattering

Abstract

A previous theory [Polym. J., 3, 67 (1972)] of light scattering by an isotropic system composed of anisotropic units is extended to the case of the out-of-plane scattering where the intensity of scattered light is measured outside the scattering-plane. Two cases are considered: the intensity is measured photoelectrically in one and photographically in the other. It is shown that the out-of-plane scattering at any direction can be reduced to the in-plane scattering with the planes of polarization of the polarizer and the analyzer inclined properly (by ψ and ω) to the vertical direction. In the photoelectric case the intensity I(ψ,ω) of the latter scattering can be expressed as I(ψ,ω)=a IVv+b IHv+c IHh+d I(45°, 45°), where IHv≡I(0°, 90°) etc. I(45°, 45°) (or some alternative) is found to give information substantially independent of those which were previously studied on IVv, IHh, and IHh. A refined method for analysis of experimental data is proposed on the basis of the four intensity functions described above. In the photographic case three photographs are shown to give all of the information, which are taken with such experimental arrangements that the plane of polarization of the polarizer is set vertical while that of the analyser is set vertical, (Vv pattern) or horizontal (Hv pattern).