what is the conclusion of devission and German experiment
Answers
The experimental discovery of diffraction of electrons by crystals by Davisson and Germer established the wave nature of electrons. The experimental setup used by them was similar to the one shown here. The setup is placed in an evacuated chamber.
In this experiment a collimated beam of electrons is incident on a nickel crystal. The electrons are scattered in various directions by the atoms of the crystal. The intensity of the electron beam, scattered in a given direction, is measured by the electron detector. By moving the detector on the circular scale at different positions the intensity of the scattered electron beam is measured for different values of angle of scattering . This experiment was performed by varying the accelerating voltage from 44 V to 68 V.
It was noticed that a strong peak appeared in the intensity I of the scattered electrons at an accelerating voltage of 54 V and at = 50°. This is due to the constructive interference of electrons scattered from different layers of the regularly spaced atoms of the crystals.