Davisson and Germer Experiment
Consider a crystal with the atoms arranged in a cubic array, each atom a distance 0.91 °A from its nearest neighbor. Examine the conditions for Bragg reflection from atomic planes connecting diagonally placed atoms. (a) Find the longest wavelength electrons that can produce a first-order maximum. (b) If 300 eV electrons are used, at what angle from the crystal normal must they be incident to produce a first order maximum?
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