Relative electric permittivity

The dielectric constant of a polymer (K) (which we also refer to as relative electric permittivity or electric inductive capacity) is a measure of its interaction with an electrical field in which it is placed. It is inversely related to volume resistivity. The dielectric constant depends strongly on the polarizability of molecules tvithin the polymer. In polymers with negligible dipole moments, the dielectric constant is low and it is essentially independent of temperature and the frequency of an alternating electric field. Polymers with polar constituents have higher dielectric constants. When we place such polymers in an electrical field, their dipoles attempt... 

Thus, we see the initial connection between optical properties and the electrical and magnetic properties from the two previous sections. Substimtion of Eqs. (6.78) and (6.79) into (6.77) shows that the refractive index can be expressed in terms of the relative electric permittivity (dielectric constant), (cf. Table 6.5), and relative magnetic permeability of the medium, (1 - - x) [cf. Eq. (6.63)], where x is the magnetic susceptibility ... 

The capacitance of the Helmholtz parallel plate capacitor per surface unit is given by Ch = e o/d, where er is the dielectric constant or the relative electric permittivity of the Hemholtz layer and e0 the electrical permittivity of free space (sq = 8.854 x 1CT12 C2 J 1 nr1) [3, 4]. 

In the absence of a strong dectric fidd (at = 0), the measured relative electric permittivity of an isotropic dielectric is a scalar quantity, defined as follows ... 

Molar Electric Polarization of Dense Media.— In Kirkwood s semi-macroscopic treatment of the linear proparties of isotropic dielectrics, one has the following relation between the relative electric permittivity Sr and the polarization P( ) induced in the medium ... 

It should be noticed that, in many theoretical works, the term solvent polarity is defined by the values of the relative electric permittivity, also called dielectric constant. However, such a definition is by no means precise. The existence of hydrogen bonds (H-bonds) between solute and solvent molecules is one of the important limitations of the use of the continuum models based on the theory of dielectrics. In modern physical chemistry of solutions in order to quantitatively describe the solvatochromism phenomenon various empirical scales of the polarity are used. The exhaustive reviews on this topic have been presented by Reichardt [1, 2],... 

We report on the determination of the complete tensor of relative electric permittivity in single crystals of pTS, as a function of temperature and polymer contents. Since the dielectric measurements prove to be a suitable method, enabling one to follow the second- order phase transition in pTS, we compare the dielectric behavior of monomer and polymer of pTS and pFBS, looking for a possible signature of a phase transition in the latter crystals. 

This expression illustrates the dependence of each factor (for a given ) on two quantities only, the relative electric permittivity and the shape of the cavity, represented here by its radius. 

Relative electric permittivity (at 27°C and 0.3 kHz) Loss tangent factor (tan5 at 140 GHz)... 

Most gases exhibit a relative electrical permittivity (i.e., dielectric constant) close to that of vacuum, that is, close to unity. Values of relative permittivity of gases may also be obtained from the data on refractive indices measured for radio frequencies by using the relation ... 

Chemical name (lUPAC) Surface tension Y(T)=A-BT Surface tension (293.15K) Thermal conductivity (293.15K) Specific heat capacity Latent enthalpy vaporization Refractive index (589nm) UV cut- off Relative electrical permittivity (293.15K) Dipole moment Henry s law constant Vapor pressure (293.15K)... 

It is more convenient to extend Eq. 2.99 to include spatial fluctuations in a. Every part of the scattering volume has naturally occurring fluctuations in the density and, for solutions, also in the concentration, as illustrated in Figure 2.47. The density and concentration are slightly different from place to place. The density fluctuations and concentration fluctuations cause fluctuations in agx through fluctuations Afij in the relative electric permittivity = e/co (also called dielectric... 

The electronic properties of the molecules have been computed by means of the MNDO method. The molecular volumes are assumed to e the samg for both tautomers in equilibrium. The values are 156.6 A and 156.8 A for the 2- and 4-hydroxypyridine systems respectively and the relative electric permittivity of water is set equal to 78. Tables 2 and 3 give the equilibrium constants and the values H of the computed... 

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