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VISUAL PHYSICS ONLINE 8.1 FROM THE UNIVERSE TO THE ATOM
THE ATOM P81 002 Discuss why neutron beams are used in determining the structure of
crystals. View solution below only after you have completed the answering the question. |
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Many
solids have a crystal structure where the atoms arrange themselves in a regular
pattern know as a crystal lattice.
A neutron beam can be used to locate the position of atoms in a
crystal It
is important in the understanding of the behaviour and properties of
materials and for the creation of new materials with special properties that
the location of the atoms is known in molecules and crystals. Beams
of very high energy particles such as neutrons can be used as probes to
investigate the structure of matter and to identify the location of atoms. To
determine the location of atoms in a crystal, the wavelength of the particle
beam must of similar magnitude of the atomic spacing within the crystal. Hence, the higher the energy (higher
velocity and momentum p = mv) of a particle, the smaller the deBroglie wavelength l = h/p. The smaller the deBroglie
wavelength, the smaller the detail that can be investigated (the better the
resolving power of a beam of such particles). |
