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BCC structure. The primitive unit cell for the body-centered cubic crystal structure contains several fractions taken from nine atoms (if the particles in the crystal are atoms): one on each corner of the cube and one atom in the center. Because the volume of each of the eight corner atoms is shared between eight adjacent cells, each BCC cell ...
Crystal structure of table salt (sodium in purple, chlorine in green). In crystallography, crystal structure is a description of ordered arrangement of atoms, ions, or molecules in a crystalline material. [1]
Density functional theory seeks to solve for an approximate form of the electronic density of a system. In general, atoms are split into ionic cores and valence electrons. The ionic cores (nuclei plus non-bonding electrons) are assumed to be stable and are treated as a single object. Each valence electron is treated separately.
Crystal structure prediction (CSP) is the calculation of the crystal structures of solids from first principles. Reliable methods of predicting the crystal structure of a compound, based only on its composition, has been a goal of the physical sciences since the 1950s. [ 1 ]
Some directions and planes have a higher density of nodes; these dense planes have an influence on the behavior of the crystal: optical properties : in condensed matter, light "jumps" from one atom to the other with the Rayleigh scattering ; the velocity of light thus varies according to the directions, whether the atoms are close or far; this ...
[1] [2] Highest density is known only for 1, 2, 3, 8, and 24 dimensions. [3] Many crystal structures are based on a close-packing of a single kind of atom, or a close-packing of large ions with smaller ions filling the spaces between them. The cubic and hexagonal arrangements are very close to one another in energy, and it may be difficult to ...
Unit cell definition using parallelepiped with lengths a, b, c and angles between the sides given by α, β, γ [1]. A lattice constant or lattice parameter is one of the physical dimensions and angles that determine the geometry of the unit cells in a crystal lattice, and is proportional to the distance between atoms in the crystal.
Series of density maps for GroEL: from left to right, 4 Å, 8 Å, 16 Å, and 32 Å resolution.The details are smeared away as the resolution becomes lower. Resolution in the context of structural biology is the ability to distinguish the presence or absence of atoms or groups of atoms in a biomolecular structure.