What is the Difference Between Bragg and Laue Diffraction?
🆚 Go to Comparative Table 🆚Bragg and Laue diffractions are two different types of diffraction techniques used in crystallography to study the structure of crystals. The main differences between them are:
- Assumptions: Bragg diffraction requires lattices that are grouped into different families of planes, and the incident radiation is specularly reflected (mirror-like). Laue diffraction, on the other hand, does not require particular planes or spacings, and the reflection does not need to be specular.
- Diffraction pattern: In Bragg diffraction, a monochromatic beam of X-rays is used, and the crystal is rotated until the angle of incidence meets the Bragg condition, resulting in a series of discrete spots on the detector, which correspond to the spacing of the crystal lattice planes. In Laue diffraction, a polychromatic beam of X-rays is used to pass through the crystal, and the X-rays are diffracted in all directions by the crystal, resulting in a continuous diffraction pattern on the detector.
- Suitability: Bragg diffraction is more suitable for studying single crystals because it produces a clear and sharp diffraction pattern that can be used to determine the crystal structure. Laue diffraction is more suitable for studying polycrystalline materials.
Both Bragg and Laue diffractions can be used for different types of crystals, including organic and inorganic crystals. However, the type of crystal and its properties may determine which diffraction technique is more suitable.
Comparative Table: Bragg vs Laue Diffraction
The main difference between Bragg and Laue diffraction lies in the way the scattered waves interfere and the information they provide about the crystal structure. Here is a table comparing the two types of diffraction:
| Feature | Bragg Diffraction | Laue Diffraction |
|---|---|---|
| Description | Bragg diffraction occurs when electromagnetic radiation or subatomic particle waves with wavelength are incident upon a crystalline sample, scattered by the atoms in the system, and undergo constructive interference in accordance with Bragg's law. | Laue diffraction relates to the scattering of waves in the process of diffraction. |
| Interference | In Bragg diffraction, the scattered waves interfere constructively, meaning they remain in phase and produce intense peaks of reflected radiation, known as Bragg peaks. | In Laue diffraction, the scattered waves interfere with each other, producing a diffraction pattern with multiple spots. |
| Crystal Structure Information | Bragg diffraction provides information about the atomic structure of the crystal, such as the lattice spacing and crystal orientation. | Laue diffraction provides information about the crystal structure, but it does not directly give the angles for coherent and incoherent scattering from a crystal lattice. |
| Equations | Bragg's law states that 2d sinθ = nλ, where d is the lattice spacing, θ is the angle between the incident ray and the scattering planes, n is an integer, and λ is the wavelength of the incident radiation. | The Laue equation relates to the scattering of waves in the process of diffraction, but it does not directly provide the angles for coherent and incoherent scattering from a crystal lattice. |
In summary, Bragg diffraction involves the interference of scattered waves constructively, producing Bragg peaks, and provides information about the atomic structure of the crystal. In contrast, Laue diffraction involves the interference of scattered waves with each other, producing multiple spots in the diffraction pattern, and does not directly provide the angles for coherent and incoherent scattering from a crystal lattice.
- Fraunhofer vs Fresnel Diffraction
- Diffraction vs Scattering
- X-ray Crystallography vs X-ray Diffraction
- Diffraction vs Refraction
- Diffraction vs Interference
- X Ray Diffraction vs Electron Diffraction
- De Broglie Wavelength vs Wavelength
- Diffraction Grating vs Transmission Grating
- Prism Spectra vs Grating Spectra
- Electron vs Neutron Diffraction
- Dichroism vs Birefringence
- Angle of Incidence vs Angle of Refraction
- X-ray Diffraction vs X-ray Fluorescence
- Rayleigh vs Raman Scattering
- Braggs Reflection vs Ordinary Reflection
- Reflection vs Refraction
- Compton Scattering vs Thomson Scattering
- Lattice vs Crystal
- Bremsstrahlung vs Cherenkov Radiation