What is anomalous dispersion?
What is anomalous dispersion?
Definition of anomalous dispersion : dispersion of light in some refraction spectra in which the normal order of the separation of components is reversed in the vicinity of certain wavelengths.
What is scattering factor in crystallography?
Definition. A measure of the scattering power of an isolated atom. Also known as the atomic form factor. The scattering factor depends on the scattering amplitude of an individual atom, on the Bragg angle and the type of radiation involved.
Which of the following parameters influence the atomic scattering factor?
The atomic scattering factor is independent of the position of the atom in the unit cell. It depends only on the type of atom and the direction of scattering, so that it reaches a maximum in the same direction of the incident X-rays, and decreases as a function of the angle of departure.
What causes anomalous dispersion?
When a beam of white light is refracted by an ordinary prism it is not only redirected; it is also dispersed. This dispersion occurs because the index of refraction depends (slightly) on the wavelength of light being refracted.
What are normal and anomalous dispersion?
In between two absorption bands, the index always increases toward shorter wavelengths. This is normal dispersion. In the absorption band itself, the index will decrease toward shorter wavelengths. This latter phenomenon is called “anomalous dispersion.” (or sometimes “resonant dispersion.”)
How do you calculate scattering factor?
The variation of the scattering factor of the carbon atom is shown in the left drawing. At the angular value corresponding to (sin θ) / λ = 0, the magnitude of the atomic scattering factor is always equal to the total number of electrons in the atom, but decreases strongly as the angular value increases.
What do you mean by scattering factor?
The atomic scattering factor (f-factor) for X-rays is the ratio of the amplitude of the X-rays scattered by a given atom and that scattered according to the classical theory by one single free electron.
What is significance of atomic scattering factor?
In physics, the atomic form factor, or atomic scattering factor, is a measure of the scattering amplitude of a wave by an isolated atom. The atomic form factor depends on the type of scattering, which in turn depends on the nature of the incident radiation, typically X-ray, electron or neutron.
What is the region of anomalous dispersion?
Normal and Anomalous Dispersion Anomalous dispersion sometimes occurs at longer wavelengths, e.g. in silica (the basis of most optical fibers) for wavelengths longer than the zero-dispersion wavelength of ≈ 1.3 μm.
Where do you get anomalous dispersion?
What is scattering factor in NDT?
What is Xray scattering factor?
What are isomorphous compounds?
(of a compound or mineral) capable of crystallizing in a form similar to that of another compound or mineral, used especially of substances so closely related that they form end members of a series of solid solutions.