Macroscopic dielectric permeability

Optical absorption in M nanocrystals embedded in dielectric matrix depends on characteristics of matrix and interface between matrix and nanocrystals. In the classical model of Mie only macroscopical dielectric permeability of environment e 2 is taken into account [16]. In this model charges at the M nanocrystal surface are determined by s2 and so frequency coa corresponding to a peak of resonant absorption is defined from a relation [18]. 

It should be noted that the given sensor is much more sensitive than a sensor based on composite films CuS-polyvinyl alcohol prepared by a classical liquid-phase method [88]. In these films the sensor effect is caused by increase in probability of tunnel transitions between CuS semiconducting particles owing to increase in macroscopical dielectric permeability of a hydrophilic matrix absorbing water from the surrounding atmosphere [88]. 

The clear derivation of the dispersion energy according to Eqs. (4.32), (4.34) from multipole contributions suggests that it is the macroscopic multipole modes rather than the molecular dipole oscillators of spheres 1 and 2 which undergo fluctuations. This becomes even more obvious if we substitute the macroscopic dielectric permeabilities i(co) and fi2( ) of materials 1 and 2 for the molecular susceptibilities Xi(co) and X2(co) according to the law of Clausius-Mosotti... 

Eq. (3.89) was derived from the general expression of the macroscopic theory for Tlyw with dielectric permeabilities, given in [148,255],... 

Experimental determination of microscopic characteristics is based on the Debye-Langevin (eq. (4.2.28)) and Lorentz-Lorentz (eq. (4.2.30)) equations. They connect macroscopic molecular characteristics, measured directly in physical experiment, with microscopic ones. Measuring dielectric permeability s in an electrostatic field, the molar polarization 11 can be found ... 

Depending on the molecular properties (e.g., the presence of dipole moments and orientation), the existence of the short- or long-range ordering in a molecule arrangement (refer to Section 9.5) and specificities of intermolecular interaction liquid crystals possess the whole scale of macroscopic properties. Practically all liquid crystals are dielectrics with strong anisotropy of electric properties, i.e., their dielectric permeability depends on direction (there are at least two value of s Sj and 8 ). In an external electric field the liquid crystal molecules are oriented in such a way Aat the direction of the maximum dielecnic permeability coincides with the external field direction. 

Dielectric permeability unit—dimensionless (a value indicating by how much an averaged macroscopic field in a dielectric is less than an external field)... 

Increase of the solvent dielectric constant caused by the compression of the solvent layer, if the concept of dielectric constant has still a meaning with such thin layers. The Microscopic Maxwell equations formalism would be more appropriate. ( Macroscopic Maxwell s equations are applied to macroscopic averages of the fields, which vary wildly on a microscopic scale closed to individual atoms. It is only in this averaged sense that one can define quantities such as the permittivity, and permeability of a material, as well as the polarization and induction field). 

The macroscopic property related to the molecular polarizability a is the dielectric constant e, defined by the ratio of the permittivity of the medium to the electric constant, cq. It is also related to the refractive index n n = y/e, assuming the vacuum magnetic permeability to be equal to 1). The quantity measured in a dielectric constant experiment is... 

In macroscopic media Maxwell s equations must be supplemented by the constitutive relations which enable the average effect of a large number of atoms to be taken into account without requiring detailed knowledge of the response of individual atoms to the effects of electric and magnetic fields. For an isotropic permeable conducting dielectric these relations are of the form ... 

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