Debye polarization

Suppose that the polar molecules are randomly distributed in the system, under an electric field those molecules tend to orientate along the direction of this electric field. The polarization induced by the orientation of the dipoles is commonly named tlie Debye polarization. For a gaseous system, Debye derived an equation for calculation of the static dielectric constant, Co, the dielectric constant extrapolated at zero frequency [6]  

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P. Debye, Polar Molecules. Chemical Catalog Co., New York, 1929. 

Dipole-Dipole Interaction. The first of the four terms in the total electrostatic energy depends on the permanent dipole moment of the solute molecule of radius a (assuming a spherical shape) immersed in a liquid solvent of static dielectric constant D. The function f(D) = 2(D - l)/(2D + 1) is known as the Onsager polarity function. The function used here is [f(D) — f(n2)] so that it is restricted to the orientational polarity of the solvent molecules to the exclusion of the induction polarity which depends on the polarizability as of the solvent molecules, related to the slightly different Debye polarity function q>(n2) according to... 

In polymer theory, the LDT result corresponds to the theory of large chain extensions P. J. Flory, Statistical Mechanics of Chain Molecules, Interscience, New York, 1969. Another mapping exists onto Debye s theory for dielectric properties of molecules with permanent dipoles P. Debye, Polar Molecules, reprinted, Dover, New York, 1958. 

For historical reasons, dipole moment or strength is often stated in Debye units (P. Debye, Polar Molecules, Dover, New York, 1929),... 

P. J. W. Debye, Polar Molecules (Dover, New York, reprint of 1929 edition) presents the fundamental theory with stunning clarity. See also, e.g., H. Frohlich, "Theory of dielectrics Dielectric constant and dielectric loss," in Monographs on the Physics and Chemistry of Materials Series, 2nd ed. (Clarendon, Oxford University Press, Oxford, June 1987). Here I have taken the zero-frequency response and multiplied it by the frequency dependence of the simplest dipolar relaxation. I have also put a> = if and taken the sign to follow the convention for poles consistent with the form of derivation of the general Lifshitz formula. This last detail is of no practical importance because in the summation Jf over frequencies fn only the first, n = 0, term counts. The relaxation time r is such that permanent-dipole response is dead by fi anyway. The permanent-dipole response is derived in many standard texts. 

The text here does not give a proper derivation of this response, only a sketch of its form. See P. J. W. Debye, Polar Molecules (Dover, New York, reprint of 1929 edition), and H. Frohlich, Theory of Dielectrics Dielectric Constant and Dielectric Loss, in Monographs on the Physics and Chemistry of Materials Series (Clarendon, Oxford University Press, 1987). 

See P. Debye, Polare Molekeln, Hirzel, 1929, for further discussion of dielectric constants. 

The unit of pressure in the constants above is the dyne per square centimeter, the unit of volume is cubic centimeters per mole. The electric moments are expressed in absolute electrostatic units. Data for Van der Waals constants and volumes are taken from Landolt s Tables for the electric moments from Debye, Polare Molekeln, Leipzig, 1929. 

P. Debye, "Polar Molecule, traslated by T. Nakamura and K. Sato, Kodansha, Tokyo (1976), p.98. 

P. Debye, Verh. Dtsch. Phys. Ges. 15, 777 (1913) reprinted in Collected Papers of Peter J. W. Debye, Interscience, New York, 1954 P. Debye, Polar Molecules, Chemical Catalog, New York 1929, reprinted by Dover Publications, New York, 1964. 

The usual computation of electric dipole moments of solute molecules is by means of formulae due to Debye ( Polar molecules . Chemical Catalog Co., 1929, 11). In our notation Debye s formulae are... 

Academic New York, 1954 4..P. Debye, Polar MAeades Dover New York, 1955. 

See for example P. Debye, Polar Molecules, New York 1929 also G. Briegleb, Zwischenmolekulare Krdfte und Molekiilstruktur, Stuttgart 1937, p. 30 compare also, A Symposium on the Dielectric Properties of Matter Chem, Rev, 19, 163-363 (1936) especially N. V. Sidgwick, ibid., p. 183 and J. G. Kirkwood, Chem, Rev., 24, 233 (1939). 

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