Polarizability is the relative tendency of a charge distribution, like the electron cloud of an atom or molecule, to be distorted from its normal shape by an external electric field, which may be caused by the presence of a nearby ion or dipole. Electron cloud is a term used if not originally coined by the Nobel Prize laureate and acclaimed educator Richard Feynman in The Feynman Lectures on Physics History See also Atomic theory, Atomism The concept that matter is composed of discrete units and cannot be divided into arbitrarily tiny In Chemistry, a molecule is defined as a sufficiently stable electrically neutral group of at least two Atoms in a definite arrangement held together by In Physics, the space surrounding an Electric charge or in the presence of a time-varying Magnetic field has a property called an electric field (that can An ion is an Atom or Molecule which has lost or gained one or more Valence electrons giving it a positive or negative electrical charge In physics there are two kinds of dipoles ( Hellènic: di(s- = two- and pòla = pivot hinge An electric dipole is a
The electronic polarizability α is defined as the ratio of the induced dipole moment of an atom to the electric field that produces this dipole moment.
Polarizability has the SI units of C·m2·V-1 = A2·s4·kg-1 but is more often expressed as polarizabilty volume with units of cm3 or in Å3 = 10-24 cm3. An ångström or angstrom (symbol Å) (ˈɔːŋstrəm Swedish: ˈɔ̀ŋstrœm is an internationally recognized non- SI unit of length equal
where ε0 is the vacuum permittivity. Permittivity is a Physical quantity that describes how an Electric field affects and is affected by a Dielectric medium and is determined by the ability
The polarizability of individual particles is related to the average electric susceptibility of the medium by the Clausius-Mossotti relation. The electric susceptibility χe of a Dielectric material is a measure of how easily it polarizes in response to an Electric field. The Clausius–Mossotti equation is named after the Italian physicist Ottaviano-Fabrizio Mossotti, whose 1850 book analyzed the relationship between the Dielectric constants
Note that the polarizability α as defined above is a scalar quantity. This implies that the applied electric fields can only produce polarization components parallel to the field. For example, an electric field in the x-direction can only produce an x component in . However, it can happen that an electric field in the x-direction, produces a y or z component in the vector . In this case α is described as a tensor of rank 2, which is represented with respect to a given system of axes (frame of reference) by a 33 matrix. History The word tensor was introduced in 1846 by William Rowan Hamilton to describe the norm operation in a certain type of algebraic system (eventually In Mathematics, a matrix (plural matrices) is a rectangular table of elements (or entries) which may be Numbers or more generally