Bragg equation

Definition

The Bragg equation, $n\lambda = 2d\sin\theta$, describes the condition for constructive interference of X-rays scattered by a crystalline lattice. It relates the wavelength of X-rays to the angle at which they are diffracted and the spacing between crystal planes.

5 Must Know Facts For Your Next Test

1. The Bragg equation is essential for determining crystal structures using X-ray diffraction.
2. In the equation $n$ is an integer representing the order of the diffraction.
3. $\lambda$ is the wavelength of the incident X-rays.
4. $d$ is the distance between atomic layers in a crystal, known as interplanar spacing.
5. $\theta$ is the angle between the incident X-ray and the scattering plane.

Review Questions

• What does each variable in the Bragg equation represent?
• How can you use the Bragg equation to determine interplanar spacing in a crystal?
• Why is it important that $n$ be an integer value in the Bragg equation?

Related terms

X-ray Diffraction:

A technique used to study atomic and molecular structure by measuring how X-rays scatter when they hit a material.

Interplanar Spacing: The distance between parallel planes of atoms in a crystal lattice.

Constructive Interference: Occurs when two or more waves combine to produce a wave with larger amplitude, key for understanding diffraction patterns.