A crystal or crystalline solid is a solid Solid is one of the major states of matter. It is characterized by structural rigidity and resistance to changes of shape or volume. Unlike a liquid, a solid object does not flow to take on the shape of its container, nor does it expand to fill the entire volume available to it like a gas does. The atoms in a solid are tightly bound to each other, material, whose constituent atoms The atom is a basic unit of matter consisting of a dense, central nucleus surrounded by a cloud of negatively charged electrons. The atomic nucleus contains a mix of positively charged protons and electrically neutral neutrons . The electrons of an atom are bound to the nucleus by the electromagnetic force. Likewise, a group of atoms can remain, molecules A molecule is defined as an electrically neutral group of at least two atoms in a definite arrangement held together by very strong chemical bonds. Molecules are distinguished from polyatomic ions in this strict sense. In organic chemistry and biochemistry, the term molecule is used less strictly and also is applied to charged organic molecules, or ions An ion is an atom or molecule in which the total number of electrons is not equal to the total number of protons, giving it a net positive or negative electrical charge. An anion , from the Greek word ἀνά (ana), meaning "up", is an ion with more electrons than protons, giving it a net negative charge (since electrons are negatively are arranged in an orderly repeating pattern extending in all three spatial dimensions. The scientific study of crystals and crystal formation is crystallography Crystallography is the experimental science of determining the arrangement of atoms in solids. In older usage, it is the scientific study of crystals. The word "crystallography" is derived from the Greek words crystallon = cold drop / frozen drop, with its meaning extending to all solids with some degree of transparency, and graphein =. The process of crystal formation via mechanisms of crystal growth The crystalline state of matter is characterized by a distinct structural rigidity and virtual resistance to deformation . 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 is called crystallization Crystallization is the process of formation of solid crystals precipitating from a solution, melt or more rarely deposited directly from a gas. Crystallization is also a chemical solid-liquid separation technique, in which mass transfer of a solute from the liquid solution to a pure solid crystalline phase occurs or solidification. The word crystal is derived from the ancient Greek Ancient Greek is the historical stage in the development of the Greek language spanning the Archaic , Classical (c. 5th–4th centuries BC), and Hellenistic (c. 3rd century BC–6th century AD) periods of ancient Greece and the ancient world. It is predated in the 2nd millennium BC by Mycenaean Greek. Its Hellenistic phase is known as Koine (" word κρύσταλλος (krustallos), which had the same meaning, but according to the ancient understanding of crystal. At root it means anything congealed by freezing, such as ice Ice is a solid phase, usually crystalline, of a non-metallic substance that is liquid or gas at room temperature, such as water, carbon dioxide ice , ammonia ice, or methane ice. However, the predominant use of the term ice is for water ice, technically restricted to one of the 15 known crystalline phases of water. In non-scientific contexts, the.[1] The word once referred particularly to quartz Quartz is the second most abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2, or "rock crystal".
Most metals encountered in everyday life are polycrystals Polycrystalline materials are solids that are composed of many crystallites of varying size and orientation. The variation in direction can be random or directed, possibly due to growth and processing conditions. Fiber texture is an example of the latter. Crystals are often symmetrically intergrown to form crystal twins Crystal twinning occurs when two separate crystals share some of the same crystal lattice points in a symmetrical manner. The result is an intergrowth of two separate crystals in a variety of specific configurations. A twin boundary or composition surface separates the two crystals. Crystallographers classify twinned crystals by a number of twin.
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