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Abstract

A theory of the dielectric constant of polar liquids has been developed by Bottcher on the basis of a simple molecular model. A molecule is represented by a sphere bearing a polarizable mathematical (point) dipole at its centre, the surroundings being treated as a homogeneous substance with the macroscopic dielectric constant. Notwithstanding its simplicity, this model gives a remarkably satisfactory description of the experimental data. In the thesis it is shown that Bottcher’s final formula still holds when the molecules are represented by a sphere with a finite dipole of arbitrary position and direction, thus contributing to the understanding as to why Bottcher’s theory is as satisfactory as it is. Finally, the energy of a molecule containing a finite arbitrarily located dipole is calculated and it is found that even for small eccentricities, the energy is considerably different from that calculated by Onsager for a point dipole at the centre of a sphere. It is indicated that this generalization helps to explain the difference between the observed and predicted results on certain polar molecules.