What is the Zimm plot?
An easy graphical way to perform data fitting corresponding to the description given in the section on the Rayleigh Ratio is the so-called Zimm plot. For small and we can equivalently write. From this equations we see that, with data for , we could plot as a function of the mass concentration.
What is the Rayleigh ratio?
[′rā·lē ‚rā·shō] (optics) Light-scattering relationship defined by the ratio of intensities of incident and scattered light at a specified distance; used in photometric and refractometric analyses.
How do you calculate light scattering?
In other words, the scattering intensity at angle θ is equal to the scattering intensity at angle 180 − θ. As a function of λ, the scattered intensity is proportional 1/λ4. This strong wavelength depen- dence makes short wavelength light scatter more than long wavelength light.
What information of a polymer does light scattering give?
Static light scattering is a technique in physical chemistry that measures the intensity of the scattered light to obtain the average molecular weight Mw of a macromolecule like a polymer or a protein in solution.
What is light scattering method?
Light scattering belongs to a class of techniques known as area-integrating methods for measuring surface texture. Rather than relying on coordinate measurements of surface points, light scattering methods probe an area of the surface and yield parameters that are characteristic of the texture of the area as a whole.
How is Rayleigh ratio calculated?
Rayleigh ratio
- For. light scattering. , dependent on the. polarization. of the incident beam, f=1 for vertically polarized light, f=1−cos2θ for horizontally polarized light and f=1+cosθ2 for unpolarized light.
- For small- angle. neutron. scattering. , f=1.
- For small- angle. X-ray. scattering. , f≈1, if θ
What is Rayleigh’s law of scattering?
Rayleigh’s scattering law The amount of scattering is inversely proportional to the fourth power of the wavelength. As sunlight travels through the earths atmosphere, it gets scattered by the atmospheric particles. Light of shorter wavelengths is scattered much more than light of longer wavelengths.
What is light scattering principle?
The basic principle is simple: The sample is illuminated by a laser beam and the fluctuations of the scattered light are detected at a known scattering angle θ by a fast photon detector. From a microscopic point of view, the particles scatter the light and thereby imprint information about their motion.