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anachin6000
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This question is as dumb and simple as it can be: Why is the path difference 2dsinθ? Or better said: Why x-ray scatters like in the image? (Couldn't there be another scattering angle for both atoms other than θ?)
sophiecentaur said:Not dumb, if you are relatively new to interference theory. Start with a large number of sources in a regular row (2 - Young's Slits - would be a way into the problem) and feed them in phase,. They will create an interference pattern with the angles of the maxima set by the wavelength and the spacing (the 2dsinθ formula). If you use an incident beam to illuminate a similarly spaced row of scattering points to try to get the same result, the only incident direction that will cause the scatterers to have a phase that's a whole number of wavelengths (equivalent to being in-phase), will be when the angle of arrival is a mirror image of the diffraction maximum. No other condition will provide the appropriate phasing of the scatterers. This is just like a mirror reflection but only for the correct angle I and R.. The deeper and wider the crystal, the sharper and better defined are the maxima. If the angle of incidence is wrong, then the scatterers do not add up coherently.
They glibly refer to the Bragg Reflection Formula but they never seemed to put it in the above way, when I learned about it. (Perhaps I just wasn't listening!)
X-Ray scattering in crystal is a technique used in crystallography to study the structure and properties of crystals. It involves shining an X-ray beam onto a crystal, which causes the beam to scatter in certain patterns based on the crystal's atomic structure.
The X-ray beam used in this technique has a wavelength similar to the size of atoms, which allows it to interact with the crystal's electrons. When the beam hits the crystal, it causes the electrons to vibrate and emit secondary x-rays at specific angles, revealing the crystal's atomic arrangement.
X-Ray scattering in crystal can provide information about the crystal's unit cell dimensions, atomic arrangement, and the distances between atoms. It can also reveal any imperfections or defects in the crystal's structure, as well as the presence of any impurities or foreign atoms.
X-Ray scattering in crystal has various applications in materials science, chemistry, and physics. It is commonly used in the pharmaceutical industry to determine the structure of drugs and their interactions with proteins. It is also used in the development of new materials, such as semiconductors and superconductors, to understand their properties and improve their performance.
Yes, there are some limitations to this technique. X-rays only interact with the electrons in a crystal, so it cannot provide information about the positions of the nuclei. It also requires a well-ordered crystal, as any disorder or impurities can affect the scattering patterns. Additionally, the crystal must be at room temperature, as extreme temperatures can alter its structure and affect the results.