Crystal chemistry is the study of the principles of chemistry behind crystals and their use in describing structure-property relations in solids. The principles that govern the assembly of crystal and glass structures are described, models of many of the technologically important crystal structures (Zinc Blende, Alumina, Quartz

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. There are many different varieties of quartz,...

, Perovskite

Perovskite

A perovskite structure is any material with the same type of crystal structure as calcium titanium oxide , known as the perovskite structure, or XIIA2+VIB4+X2−3 with the oxygen in the face centers. Perovskites take their name from this compound, which was first discovered in the Ural mountains of...

) are studied, and the effect of crystal structure on the various fundamental mechanisms responsible for many physical properties are discussed.

The objectives of the field include:

1. identifying important raw materials and minerals as well as their names and chemical formulae.
2. describing the crystal structure of important materials and determining their atomic models.
3. learning the systematics of crystal and glass chemistry.
4. understanding how physical and chemical properties are related to crystal structure
   Crystal structure
   In mineralogy and crystallography, crystal structure is a unique arrangement of atoms or molecules in a crystalline liquid or solid. A crystal structure is composed of a pattern, a set of atoms arranged in a particular way, and a lattice exhibiting long-range order and symmetry...
   
    and microstructure.
5. studying the engineering significance of these ideas and how they relate to industrial products: past, present, and future.

Topics studied are:

1. Chemical bond
   Chemical bond
   A chemical bond is an attraction between atoms that allows the formation of chemical substances that contain two or more atoms. The bond is caused by the electromagnetic force attraction between opposite charges, either between electrons and nuclei, or as the result of a dipole attraction...
   
   ing, Electronegativity
   Electronegativity
   Electronegativity, symbol χ , is a chemical property that describes the tendency of an atom or a functional group to attract electrons towards itself. An atom's electronegativity is affected by both its atomic number and the distance that its valence electrons reside from the charged nucleus...
   
   
2. Fundamentals of crystallography
   Crystallography
   Crystallography is the experimental science of the arrangement of atoms in solids. The word "crystallography" derives from the Greek words crystallon = cold drop / frozen drop, with its meaning extending to all solids with some degree of transparency, and grapho = write.Before the development of...
   
   : crystal systems, Miller Indices, symmetry elements, bond lengths and radii, theoretical density
3. Crystal and glass structure prediction: Pauling’s
   Pauling's rules
   Pauling's rules are five rules published by Linus Pauling in 1929 for determining the crystal structures of complex ionic crystals.-First rule:...
   
    and Zachariasen’s rules
4. Phase diagrams and crystal chemistry (including solid solution
   Solid solution
   A solid solution is a solid-state solution of one or more solutes in a solvent. Such a mixture is considered a solution rather than a compound when the crystal structure of the solvent remains unchanged by addition of the solutes, and when the mixture remains in a single homogeneous phase...
   
   s)
5. Imperfections (including defect chemistry and line defects
   Crystallographic defect
   Crystalline solids exhibit a periodic crystal structure. The positions of atoms or molecules occur on repeating fixed distances, determined by the unit cell parameters. However, the arrangement of atom or molecules in most crystalline materials is not perfect...
   
   )
6. Phase transitions
7. Structure – property relations: Neumann’s law
   Neumann's law
   Neumann's Law states that the molecular heat in compounds of analogous constitution is always the same. It is named after Franz Ernst Neumann.- References :...
   
   , melting point, mechanical properties (hardness, slip, cleavage
   Cleavage (crystal)
   Cleavage, in mineralogy, is the tendency of crystalline materials to split along definite crystallographic structural planes. These planes of relative weakness are a result of the regular locations of atoms and ions in the crystal, which create smooth repeating surfaces that are visible both in the...
   
   , elastic moduli), wetting
   Wetting
   Wetting is the ability of a liquid to maintain contact with a solid surface, resulting from intermolecular interactions when the two are brought together. The degree of wetting is determined by a force balance between adhesive and cohesive forces.Wetting is important in the bonding or adherence of...
   
   , thermal properties (thermal expansion, specific heat, thermal conductivity
   Thermal conductivity
   In physics, thermal conductivity, k, is the property of a material's ability to conduct heat. It appears primarily in Fourier's Law for heat conduction....
   
   ), diffusion, ionic conductivity
   Ionic conductivity
   Ionic conduction is the movement of an ion from one site to another through defects in the crystal lattice of a solid. Ionic conduction is one aspect of current....
   
   , refractive index
   Refractive index
   In optics the refractive index or index of refraction of a substance or medium is a measure of the speed of light in that medium. It is expressed as a ratio of the speed of light in vacuum relative to that in the considered medium....
   
   , absorption
   Absorption (electromagnetic radiation)
   In physics, absorption of electromagnetic radiation is the way by which the energy of a photon is taken up by matter, typically the electrons of an atom. Thus, the electromagnetic energy is transformed to other forms of energy for example, to heat. The absorption of light during wave propagation is...
   
   , color, Dielectrics and Ferroelectrics
   Ferroelectricity
   Ferroelectricity is a property of certain materials which possess a spontaneous electric polarization that can be reversed by the application of an external electric field. The term is used in analogy to ferromagnetism, in which a material exhibits a permanent magnetic moment. Ferromagnetism was...
   
   , and Magnetism
   Magnetism
   Magnetism is a property of materials that respond at an atomic or subatomic level to an applied magnetic field. Ferromagnetism is the strongest and most familiar type of magnetism. It is responsible for the behavior of permanent magnets, which produce their own persistent magnetic fields, as well...
   
   
8. Crystal structures of representative metals, semiconductors, polymers, and ceramics