A crystal is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. Crystal growth is a major stage of a crystallization process, and consists in the addition of new atoms, ions, or polymer strings into the characteristic arrangement of a crystalline Bravais lattice. The growth typically follows an initial stage of either homogeneous or heterogeneous (surface catalyzed) nucleation, unless a "seed" crystal, purposely added to start the growth, was already present.
The action of crystal growth yields a crystalline solid whose atoms or molecules are typically close packed, with fixed positions in space relative to each other. The crystalline state of matter is characterized by a distinct structural rigidity and virtual resistance to deformation (i.e. changes of shape and/or volume). Most crystalline solids have high values both of Young's modulus and of the shear modulus of elasticity. This contrasts with most liquids or fluids, which have a low shear modulus, and typically exhibit the capacity for macroscopic viscous flow.
Read more about Crystal Growth: Introduction, Discontinuity, Nucleation, Mechanisms of Growth, Morphology
Famous quotes containing the words crystal and/or growth:
“Shall we gather at the river,
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With its crystal tide for ever,
Flowing by the throne of God?”
—Robert Lowry (1826–1899)
“Here commences what was called, twenty years ago, the best timber land in the State. This very spot was described as “covered with the greatest abundance of pine,” but now this appeared to me, comparatively, an uncommon tree there,—and yet you did not see where any more could have stood, amid the dense growth of cedar, fir, etc.”
—Henry David Thoreau (1817–1862)