LEED: Principle of operation:

The typical intensity profile obtained for this case is shown in Figure 7.04.

Figure 7.04: Intensity profile pattern with the angle, θ.

(1) the pattern is symmetric about θ = 0 (or sinθ = 0)
(2) Since λ ∝ 1/(V ^1/2), sinθ∝ 1/(V^1/2)
(3) sinθ is also inversely proportional to the lattice parameter, a

This reveals that all surface diffraction patterns show a symmetry reflecting that of the surface structure and of a scale showing an inverse relationship to both the square root of the electron energy and the size of the surface unit cell.