Bragg plane

In physics, a Bragg plane is a plane in reciprocal space which bisects a reciprocal lattice vector, ${\displaystyle \scriptstyle \mathbf {K} }$, at right angles. The Bragg plane is defined as part of the Von Laue condition for diffraction peaks in x-ray diffraction crystallography.

Considering the diagram on the right, the arriving x-ray plane wave is defined by:

Where ${\displaystyle \scriptstyle \mathbf {k} }$ is the incident wave vector given by:

where ${\displaystyle \scriptstyle \lambda }$ is the wavelength of the incident photon. While the Bragg formulation assumes a unique choice of direct lattice planes and specular reflection of the incident X-rays, the Von Laue formula only assumes monochromatic light and that each scattering center acts as a source of secondary wavelets as described by the Huygens principle. Each scattered wave contributes to a new plane wave given by:

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