braggs law
When x-rays are scattered from a crystal lattice, peaks of scattered intensity are observed which correspond to the following conditions:- The angle of incidence = angle of scattering.
2.The pathlength difference is equal to an integer number of wavelengths
Bragg's Law: nλ = 2d sinθ
Where d is the distance between atomic layers in a crystal, λ is the wavelength in metres of the incident beam, θ is the angle of incidence, n is an integer representing the number of wavelengths required for constructive
interference to occur. At the smallest angle of incidence (θ) for a maxima n = 1, at the
next smallest angle n = 2, etc.
Bragg’s Law is an example of X-ray wave interference or X-ray diffraction (XRD),
and is used to determine the atomic structure of crystals.
The Braggs were awarded the Nobel Prize in physics in 1915 for their work in
determining crystal structures (NaCl)
use of braggs law-
Although Bragg's law was used to explain the interference pattern of X-rays scattered
by crystals, diffraction has been developed to study the structure of all kinds of matter
with a beam, as long as the wavelength used is comparable to the spacing of the
molecules (or atoms) within the object under investigation.
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