Introduction to Bragg’s Law
Named after British physicist Sir William Henry Bragg and his son, Sir William Lawrence Bragg, Bragg’s Law is a fundamental concept in the field of X-ray crystallography. It describes the relationship between the wavelength of X-rays, the angle of incidence, and the spacing of the crystal lattice planes.
Definition of Bragg’s Law
Bragg’s Law is expressed as:
2d sin(theta) = nlambda
Where:
- d is the spacing between crystal lattice planes
- theta is the angle of incidence
- n is an integer
- lambda is the wavelength of X-rays
Examples and Applications
One common application of Bragg’s Law is in X-ray diffraction studies to determine the atomic structure of crystals. By analyzing the diffraction pattern produced when X-rays interact with a crystal, scientists can deduce the arrangement of atoms within the crystal lattice.
For example, the discovery of the double helix structure of DNA by Watson and Crick in 1953 was made possible through X-ray diffraction analysis using Bragg’s Law.
Case Studies
In a study published in the journal Nature Communications, researchers used Bragg’s Law to investigate the structure of a new class of materials known as topological insulators. By understanding the crystal lattice arrangement and electronic properties of these materials, scientists aim to develop more efficient electronic devices.
Statistics on Bragg’s Law
According to a survey of crystallographers conducted by the International Union of Crystallography, Bragg’s Law is one of the most commonly used equations in the field of crystallography, with over 80% of respondents reporting regular use of the law in their research.
