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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.

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. The re-emitted wave fields interfere with each other either constructively or destructively, producing the diffraction pattern on a detector or film.

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How can I find a very old paper by W.L. Bragg from 1913?

I'm often looking for old physics papers that had a big impact on science (Nobel prize, for example). But I can't seem to find a lot of them. Is there a reason why some papers are not digitally available, but others (that had less impact)…
Foo Bar
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Clarification about Bragg's law explanation

The Wikipedia has this illustration of Bragg's law and then says The two separate waves will arrive at a point with the same phase, and hence undergo constructive interference, if and only if this path difference is equal to any integer value of…
user114806
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Origin of Laue equations?

The Bragg condition (by Bragg in 1913) can be derived by the Laue equations that is making use of the Miller indices and all the latice/crystal stuff (so basically it's bringing Bragg's law to more fundamental ground). But what is interesting to me:…
Foo Bar
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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 trajectories from different atoms (from the same row)…
TheScientist
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X-Ray diffraction - Braggs law

"Based on the Bragg equation, if crystal A has larger spacing in its diffraction pattern than crystal B, what conclusion can you draw about the spacing between layers of atoms in A compared with B?" I have been looking at this problem for quite…
Thomas Mcinally
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Neutron diffraction on Salty Ice VII

Can someone explain in layman's term how this figure shows the presence of Cl and Li ions in Ice VII ? What can we deduce about the crystal from this data ? The whole figure and caption are available here…
mwa1
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How to identify a crystal structure by its x-ray reflection bragg angles?

How to identify a crystal structure by its x-ray reflection bragg angles? Suppose we have a crystal sample to examine its crystal structure (e.g. SC, BCC, FCC, etc). What we can get from an X-ray diffraction experiment is the incidence beam wave…
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Diffraction/Bragg's law : how does $2\theta$ come about?

I'm trying to get my head around a problem (I should have checked whether I had the answer in class, the exams are coming up now and I don't know if I'll get a lecturer response over the holidays) I can't get figure out the relationship between…
Louis Maddox
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Is coherent source needed to observe Bragg diffraction?

In undergraduate solid state physics, derivations of Bragg scattering are often short and scarce in detail, often resorting to virtual "lattice planes" (which I do not find convincing) or Huygens's Principle, like in this image from Wikipedia: This…
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Path difference between scattered x-rays

My textbook, Solid-State Physics, Fluidics, and Analytical Techniques in Micro- and Nanotechnology, by Madou, says the following in a section on X-Ray Intensity and Structure Factor $F(hkl)$: We now mathematically derive the intensity profile of…
The Pointer
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Derivation of Laue equations

The Wikipedia article for the Laue equations presents them as follows: Let $\mathbf{a}\, ,\mathbf{b}\, ,\mathbf{c}$ be the primitive vectors of the crystal lattice $L$, whose atoms are located at the points $\mathbf x = p\,\mathbf a+q\,\mathbf…
The Pointer
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Equivalent representations of path difference? (Laue equations and Bragg's law)

My textbook, Solid-State Physics, Fluidics, and Analytical Techniques in Micro- and Nanotechnology, by Madou, presents the following image and explanation in a section on x-ray diffraction and Laue equations: Constructive interference will occur…
The Pointer
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Bragg condition for transmission: Why is the full diffracted angle Two times Theta? Or isn't it?

On a Bragg reflection with incomming angle Theta the total diffraction angle of the incomming wave is 2*Theta, of course. But I have Bragg transmission with electrons on a graphite crystal (experiment about de-Broglie-wavelength and…
Foo Bar
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Confusion about interference of light in Bragg's experiment

My current understanding of Bragg's experiment is this: A collimated X ray beam was shone to the surface of a metal. If we model a metal as an aggregate of parallel planes, one X ray reflects off one layer, then another X ray reflects off a layer…
user166520
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Can time crystals scatter incoming waves toward the past?

Can time crystals scatter incoming waves toward the past? I think it is a fair question to ask, albeit the answer is overwhelmingly likely NO. But since the concept is fairly new, I'm wondering if there could be on the horizon an experimental setup…
lurscher
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