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:
“Wise men read very sharply all your private history in your look and gait and behavior. The whole economy of nature is bent on expression. The tell-tale body is all tongues. Men are like Geneva watches with crystal faces which expose the whole movement.”
—Ralph Waldo Emerson (1803–1882)
“The Past—the dark unfathom’d retrospect!
The teeming gulf—the sleepers and the shadows!
The past! the infinite greatness of the past!
For what is the present after all but a growth out of the past?”
—Walt Whitman (1819–1892)