I Is There an Analogous Law for X-ray Diffraction Minima?

L_landau
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For x-day diffraction maxima we have braggs law
2d*sinθ = mλ (maxima)

Is there an analogous law for the minima like
2d*sinθ = (m+1/2)λ (minima?)

Thanks!
 
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Diffraction gratings don't have a simple alternating maximum/minimum pattern like the two-slit setup does.

http://hyperphysics.phy-astr.gsu.edu/hbase/phyopt/gratint.html

What you see are the primary maxima which are very narrow and bright. You don't normally see the secondary maxima and the minima in between them.
 
For an ideal, infinite crystal, and using the kinematic theory of x-ray diffraction, there is intensity only at the Bragg positions, and nothing in between. Once you consider real (finite and imperfect) crystals and multiple scattering (dynamical theory of x-ray diffraction), things become a bit more complicated.

As an example, in surface diffraction, you get something called an "anti-Bragg" position.

https://en.wikipedia.org/wiki/X-ray_crystal_truncation_rod
 
Hi. I have got question as in title. How can idea of instantaneous dipole moment for atoms like, for example hydrogen be consistent with idea of orbitals? At my level of knowledge London dispersion forces are derived taking into account Bohr model of atom. But we know today that this model is not correct. If it would be correct I understand that at each time electron is at some point at radius at some angle and there is dipole moment at this time from nucleus to electron at orbit. But how...
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