What is the procedure in Davisson-Germer experiment?

Answer 1

The Davisson-Germer experiment demonstrated the wave nature of the electron, confirming the earlier hypothesis of de Broglie. Putting wave-particle duality on a firm experimental footing, it represented a major step forward in the development of quantum mechanics. The Bragg Lawfor diffraction had been applied to x-ray diffraction, but this was the first application to particle waves.

Davisson and Germer designed and built a vacuum apparatus for the purpose of measuring the energies of electrons scattered from a metal surface. Electrons from a heated filament were accelerated by a voltage and allowed to strike the surface of nickel metal. The electron beam was directed at the nickel target, which could be rotated to observe angular dependance of the scattered electrons. Their electron detector (which was also called as a Faraday box) was mounted on an arc so that it could be rotated to observe electrons at different angles. It was a great surprise to them to find that, at certain angles there was a peak in the intensity of the scattered electron beam. This peak indicated wave behaviour for the electrons, and could be interpreted by the Bragg Law to give values for the lattice spacing in the nickel crystal.

Answer 2

In the Davisson-Germer experiment, electrons are accelerated through a potential difference towards a nickel crystal target. When the electrons strike the target, they scatter off the atoms in the crystal and create a diffraction pattern of intensity peaks that can be observed on a fluorescent screen. By analyzing the diffraction pattern, information about the crystal structure and the wave nature of electrons can be deduced.