X ray diffraction
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X-ray diffraction is a technique used to determine the atomic and molecular structure of crystals. When an X-ray beam hits a crystal, the beam diffracts into specific directions based on the atomic planes in the crystal. Bragg's law describes the diffraction pattern and is used to explain the angles and wavelengths of the diffracted X-rays. To collect diffraction data, crystals are mounted on a goniometer and bombarded with X-rays while being rotated, producing a diffraction pattern. The pattern can then be analyzed to determine information about the crystal structure like lattice parameters and atomic arrangement.
X ray diffraction
- 1. X-Ray Diffraction Praveen Kumar Central University of Bihar School of Earth Biological and Environmental Sciences
- 2. An electromagnetic wave of high energy and very short wavelength (between ultraviolet light and gamma rays), which is able to pass through many materials opaque to light. Energy : 100 eV to 100keV Wavelength : 0.01 to 10 nanometer X Ray Why are x- rays used? λ ~ Å
- 3. The process by which a beam of light or other system of waves is spread out as a result of passing through a narrow aperture or across an edge, typically accompanied by interference between the wave forms produced. Diffraction
- 4. X Ray Diffraction A technique used to determine the atomic and molecular structure of a crystal, in which the crystalline atoms cause a beam of incident X-rays to diffract into many specific directions. The atomic planes of a crystal cause an incident beam of X- rays to interfere with one another as they leave the crystal. The phenomenon is called X-ray diffraction. A stream of X-rays directed at a crystal diffract and scatter as they encounter atoms. The scattered rays interfere with each other and produce spots of different intensities that can be recorded on film.
- 5. Working Principle Bragg’s Law Bragg's law was used to explain the interference pattern of X-rays scattered by crystals Nλ = 2dhkl sinθ q q dhkldhkl
- 7. How Does It WorkSource:http://en.wikipedia.org/wiki/File:X_ray_diffraction.png Crystal (regular array of atoms) is mounted on a Goniometer Bombarded with X-Ray while rotating Production of diffraction pattern of regularly spaced spots The 2-D images taken at different rotation are converted to 3-D models of the electron density map by the method of Fourier Transform
- 9. Uses XRD is a non-destructive technique. To determine structural properties such as Lattice parameters (10-4Å), strain, grain size Biological macromolecular crystallography To determine atomic arrangement. To measure thickness of thin films and multi-layers.
- 10. Thanks