Af appeared to be well suited for the study of these matters, since it is a normal paramagnet, with three unpaired electrons on the chromium, its crystal structure is very simple, and the unknown position of the hydrogen in the strong Af bond provides structural interest.

Douglass has studied the crystal structure of Af by x-ray diffraction.

It has the same crystal structure as red phosphorus and black arsenic, it oxidizes in air and may ignite spontaneously.

Most metals and alloys can be work hardened by creating defects in their crystal structure.

This causes the iron crystals to deform intrinsically when the crystal structure tries to change to its low temperature state, inducing great hardness.

These intermetallic alloys appear homogeneous in crystal structure, but tend to behave heterogeneous, becoming hard and somewhat brittle.

A perfect crystal is one in which the internal lattice structure extends uninterrupted in all directions.

* Interactive 3D-structure of aspirin with detailed x-ray crystal structure

In the early 20th century it was recognized that other cases such as carbon were due to differences in crystal structure.

As of 2012, no crystal structure is available for class I AC.

They contain only one phase, with face-centered cubic crystal structure.

Beryllium is a steel gray and hard metal that is brittle at room temperature and has a close-packed hexagonal crystal structure.

* Basis ( crystal structure ), the positions of the atoms inside the unit cell

The crystal has a double-hexagonal close packing structure with the layer sequence ABAC and so is isotypic ( having a similar structure ) with α-lanthanum and α-forms of actinides beyond curium.

This crystal structure changes with pressure and temperature.

An example of a 4-stranded Antiparallel ( biochemistry ) | antiparallel β sheet fragment from a crystal structure of the enzyme catalase ( PDB file 1GWE at 0. 88Å resolution ).

The scientific definition of a " crystal " is based on the microscopic arrangement of atoms inside it, called the crystal structure.

A crystal structure ( an arrangement of atoms in a crystal ) is characterized by its unit cell, a small imaginary box containing one or more atoms in a specific spatial arrangement.

As a halite crystal is growing, new atoms can very easily attach to the parts of the surface with rough atomic-scale structure and many dangling bonds.

This is determined by the crystal structure ( which restricts the possible facet orientations ), the specific crystal chemistry and bonding ( which may favor some facet types over others ), and the conditions under which the crystal formed.

The crystal lattice of solid americium and its compounds contains intrinsic defects, which are induced by self-irradiation with alpha particles and accumulate with time ; this results in a drift of some material properties.

The structures are made from a golden material, and are capped with a crystal that replicates the atmospheric conditions of the Masters ' home planet.

A crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an ordered pattern extending in all three spatial dimensions.

A supercooled liquid behaves as a liquid, but it is below the freezing point of the material, and in some cases will crystallize almost instantly if a crystal is added as a core.

In this process, ions are implanted at a high enough energy and dose into a material to create a layer of a second phase, and the temperature is controlled so that the crystal structure of the target is not destroyed.

The surface of the electrodes that are in contact with the liquid crystal material are treated so as to align the liquid crystal molecules in a particular direction.

Both the liquid crystal material and the alignment layer material contain ionic compounds.

* In 1962, Richard Williams of RCA found that liquid crystals had some interesting electro-optic characteristics and he realized an electro-optical effect by generating stripe-patterns in a thin layer of liquid crystal material by the application of a voltage.

The ordering in a liquid crystal might extend along only one dimension, with the material being essentially disordered in the other two directions.

In this formalism, a liquid crystal material is treated as a continuum ; molecular details are entirely ignored.

Thermotropic chiral LCs whose pitch varies strongly with temperature can be used as crude liquid crystal thermometers, since the color of the material will change as the pitch is changed.

* Semiconductors, a type of solid, crystal with uniform dopant distribution or material with differing dopant levels in which the movement of electrons can cause laser action.

The manufacture of a perfect crystal of a material is currently physically impossible.

In single crystal form, silicon is an almost perfect Hookean material, meaning that when it is flexed there is virtually no hysteresis and hence almost no energy dissipation.

Glasses are amorphous solids ( e. g. amorphous materials that are at temperatures below the glass transition temperature ) which are usually fabricated when the viscous molten material cools very rapidly to below its glass transition temperature, without sufficient time for a regular crystal lattice to form.

* Crystallography is an unambiguous method for determining molecular geometry, the proviso being that single crystals of the material must be available and the crystal must be representative of the sample.

* Photonic crystal, a photonic band gap material

* Polymorphism ( materials science ), the ability of a solid material to exist in more than one form or crystal structure

The strain-charge for a material of the 4mm ( C < sub > 4v </ sub >) crystal class ( such as a poled piezoelectric ceramic such as tetragonal PZT or BaTiO < sub > 3 </ sub >) as well as the 6mm crystal class may also be written as ( ANSI IEEE 176 ):

For them the stress can be imagined to transform the material from a non-polar crystal class ( P

A donor atom that activates ( that is, becomes incorporated into the crystal lattice ) donates weakly bound valence electrons to the material, creating excess negative charge carriers.

Therefore, a silicon crystal doped with boron creates a p-type semiconductor whereas one doped with phosphorus results in an n-type material.