solids exist in the crystalline and amorphous states, and preferably have a crystalline structure.It is characterized by correct location of particles in precisely defined points is characterized by periodic recurrence in volumetric, three-dimensional space.If you mentally connect these points with straight - get the space frame, which is called a crystal lattice.The term "crystalline lattice" refers to a geometric pattern which describes a three-dimensional periodicity in placing molecules (atoms, ions) in the crystal area.
at the location of particle called the lattice sites.Inside the frame are inter-node communication.Type particles and the nature of relations between them: molecules, atoms, ions - determine the type of the crystal lattice.In total there are four of these types: ionic, atomic, molecular and metallic.
If the lattice sites are located ions (particles with a negative or positive charge), this ion crystal lattice, characterized by the same name constraints.
These links are extremely durable and stable.Therefore, with this type of material structure have a sufficiently high hardness and density, non-volatile and refractory.At low temperatures, they behave as insulators.However, the melting of these compounds is broken geometrically correct ion crystal lattice (the arrangement of the ions) and reduced strength due.
at temperatures close to the melting temperature, ionic crystals, are already capable of conducting an electric current.Such compounds are readily soluble in water and other liquids, which are composed of polar molecules.
ionic crystal lattice characteristic of all substances with ionic bonds - salt, metal hydroxides, binary compounds of metals with non-metals.The ionic bond does not have a direction in space, because each ion is associated with several counter-interaction force depends on the distance between them (Coulomb's law).Ion-related compounds have non-molecular structure, they are solids with ionic lattices, highly polar, high melting points and boiling in aqueous solution, are electrically conductive.Compounds with ionic bonds in pure form practically does not occur.
ionic crystal lattice has some hydroxide and oxide of typical metal salts, ie,Substances with an ionic chemical bond.
addition of ionic bonding in crystals is metallic, molecular and covalent bond.
Crystals having a covalent bond, are semiconductors and dielectrics.Typical examples of the atomic crystals are diamond, silicon and germanium.
diamond - a mineral allotropic cubic modification (form) of carbon.The crystal lattice of diamond - nuclear, very complicated.The nodes of a lattice atoms are connected by a very strong covalent bonds.Diamond is composed of individual carbon atoms arranged one in the center of the tetrahedron whose vertices are the four neighboring atoms.Such a lattice is characterized by a face-centered cubic unit cell, resulting in a maximum hardness of diamond and a relatively high melting point.The diamond lattice there are no molecules - and the crystal can be regarded as one imposing molecule.
In addition, the atomic crystal lattice characteristic of silicon solid forest, Germany and the individual elements with silicon and carbon (silica, quartz, mica, river sand, silicon carbide).In general, the representatives of crystalline solids with relatively few atomic lattice.
