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A C B Figure 1. 1. Scattering of two beams at angle 0 from two planes in a crystal spaced by d The importance of these x-ray scattering experiments to electrons and nuclei appears in the experiments of Davisson and Germer in 1927 who scattered electrons of (reasonably) fixed kinetic energy E from metallic crystals. These workers found that plots of the number of scattered electrons as a function of scattering angle 0 displayed"peaks at angles 0 that obeyed a Bragg-like equation. The startling thing about this observation is that electrons are particles, yet the Bragg equation is based on the properties of waves An important observation derived from the Davisson-Germer experiments was that the scattering angles 0 observed for electrons of kinetic energy e could be fit to the bragg n n= 2d sine equation if a wavelength were ascribed to these electrons that was defined by3 Figure 1.1. Scattering of two beams at angle q from two planes in a crystal spaced by d. The importance of these x-ray scattering experiments to electrons and nuclei appears in the experiments of Davisson and Germer in 1927 who scattered electrons of (reasonably) fixed kinetic energy E from metallic crystals. These workers found that plots of the number of scattered electrons as a function of scattering angle q displayed “peaks” at angles q that obeyed a Bragg-like equation. The startling thing about this observation is that electrons are particles, yet the Bragg equation is based on the properties of waves. An important observation derived from the Davisson-Germer experiments was that the scattering angles q observed for electrons of kinetic energy E could be fit to the Bragg n l = 2d sinq equation if a wavelength were ascribed to these electrons that was defined by
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