# Questions tagged [braggs-law]

Condition for the angles for coherent and incoherent scattering from a crystal lattice, summarizing the diffractive interference pattern dictated by the geometry of the lattice. Normally for Rayleigh scattering (elastic scattering) of X-rays off atom lattices; but also for scattered neutron waves from nuclei or by a coherent spin interaction with an unpaired electron.

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### Unique lattice constant using X-ray diffraction

I recently learned about X-diffraction methods to analyse crystal lattices. One important law in this is the Bragg condition $$\lambda = 2d\sin(\theta).$$ I understand that $d$ is the distance between ...
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### Why a crystal lattice with short axes would have a diffraction pattern in which spots would appear far apart using Bragg's law?

With the aid of Bragg's law, explain why a crystal lattice with short axes would have a diffraction pattern in which spots would appear far apart?
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### How to determine the interplanar distance from the Miller Indeces $(h k l)$ of different lattices

I know that for cubic unit cells, there is a simple correspondence between the interplanar distance and the Miller Indeces: $d=\frac{1}{\sqrt{h^2 + k^2 + l^2}}$ What happens when we have more complex ...
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### Why does Bragg's law consider only specular scattering for constructive interference?

My textbook only considers two-dimensional scattering, so I will stick to that. When explaining Bragg's law, it states that the incidence angle and the scattering angle must be equal so that all ...
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### Monochromator crystal

A monochromator crystal is often used to select a specific energy value in a polychromatic beam of X-rays or neutrons. It exploits Bragg's law that (in the von Laue formulation) states that a crystal ...
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### How can the waves interfere in X-ray diffraction?

This is the popular diagram surrounding the Bragg's law for X ray diffraction: But what I seem to not be able to understand is when they say that the reflected waves interact constructively to create ...
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### What is the smallest value of the incident angle in Bragg's law?

The title of my question basically is what I want to know. In Bragg's law, $nλ = 2 d \sin{\theta}$, if we want to find, let's say, $d$, and know only $\lambda$ and $n$, but not $\theta$, what could be ...
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### What is the catch behind the simple expression and explanation of Bragg's Law?

Consider how the topic of scattering by periodic crystal structures is covered in most books: Start by treating the crystal structure as a periodic potential and use Fermi's Golden Rule to show that ...
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### Coherent and incoherent electron diffraction

I am learning about electron diffraction in a transmission electron microscope and was wondering about following topic: A single crystalline material will exhibit a diffraction pattern with discrete ...
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### Why is Bragg's Law always presented as $n\lambda=2d\sin \theta$?

In the vast majority of texts and handbooks on Bragg diffraction, Bragg's formula is presented as: $$n\lambda=2d\sin \theta\tag{1}$$ where $\theta$ is the incident angle. But constructive interference ...
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### Can raman be used to know the number of layers other than graphene?

I came across some paper where the number of layers of Graphene have been investigated by Raman spectroscopy. I found simulation websites https://instanano.com/characterization/calculator/raman/...
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### Laser diffraction by synthetic Opal: how to determine "$d$"?

I'm doing some measurements with laser diffraction on a cut cube of synthetic opal. Here's a stock photo of it: The shimmering colours are due to diffraction of visible light on intermolecular planes ...
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### Minimum distance for two parallel beam to interfere effectively

Following is an illustration of two parallel monochromatic beams interfering in Bragg's law experiment. For these two rays to interfere, what is the minimum distance OF required? I understand that the ...
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