Bravais single-crystalline lattice

Assuming Markovian diffusion on a Bravais single-crystalline lattice, the intermediate scattering function is given by... 

In case of harmonic solids with Debye-like low-frequency dynamics and vibrational isotropy, that is, polycrystalline sample, or single-crystalline one with a cubic Bravais lattice, the Debye velocity of sound vd can be precisely determined from the expression [107]... 

The existence of crystals has provided a tremendous boost to the study of solids, since a crystalline solid can be analyzed by considering what happens in a single unit of the crystal (referred to as the unit cell), which is then repeated periodically in all three dimensions to form the idealized perfect and infinite solid. The unit cell contains typically one or a few atoms, which are called the basis. The points in space that are equivalent by translations form the so called Bravais lattice. The Bravais lattice and the basis associated with each unit ceU detennine the crystal. This regularity has made it possible to develop powerful analytical tools and to use clever experimental techniques to study the properties of solids. 

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