Davisson

Davisson

Davidson (right) and his colleague grimmer's experiments were made with cubic crystals of nickel. Instead of using the surface of the cubic crystal as the incident plane of electrons, they symmetrically cut off an angle of the cubic crystal to form a triangular plane and use it as the incident plane of electrons. Let a beam of electrons shoot directly at the incident plane at a predetermined speed, and the crystal itself rotates with the incident electron beam as the axis, so that the elastic scattering intensity in any direction in front of the crystal plane can be measured. Because the atomic spacing in crystal has been determined by X-ray experiment, the material wave length of electron can be calculated according to the angle of diffraction electron beam and crystal constant. It is found that the wavelength obtained from the diffraction data is consistent with that calculated from the de Broglie relation L = H / P.