![]() ![]() A flat photographic film is placed to receive a transmitted diffracted beam. A single crystal specimen of dimensions of is held stationary in the beam of X-rays. A pinhole arrangement produces a collimated beam of X-rays. In this method, an X-ray source is used that produces X-ray beam having a wide range of wavelengths from to. Laue Method: This method of x-ray diffraction uses a flat plate x-ray camera and a fine beam of X-rays. There are three methods used to analyze the structure of a crystal namely, the Laue method, rotating crystal method, and powder method.ġ. The wavelength of the incident beam must not be greater than twice the spacing of crystal planes. X-ray diffraction takes place when this condition is satisfied. This is the condition for maximum reflection of the incident beam of X-rays and called Bragg’s law. When X-ray beam of wavelength is incident on the planes and the path difference is an integral multiple of the wavelength, then for the constructive interference of the incident rays, becauseī C = C D = d sin θ BC = CD = d\sin \theta B C = C D = d sin θĢ d sin θ = n λ 2d\sin \theta = n\lambda 2 d sin θ = n λ Path Difference = B C C D = BC CD Path Difference = B C C D When a beam of X-rays is incident on a set of parallel atomic planes in a crystal that is spaced at an equal distance of ‘d’, the path difference between the reflected rays is represented as, Bragg assumed that reflection of X-rays from parallel planes of atoms in a crystal is a regular or specular reflection. Bragg gave the condition for x-ray diffraction. ![]()
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