135 We first describe the thermodynamic theory of surface tension and adsorption, by the method of the dividing surface of GIBBS. The use of a dividing surface or its equivalent is indispensable for the treatment of a curved interface, as otherwise the concepts of the area and curvature of the interface, cannot be pre­ cisely defined. In the case of a plane interface, however, the concept of the dividing surface is not necessary and a valid alternative exposition has been proposed by GUGGEN­ HEIM [3J, [4J in treating the interface zone as a separate entity of some definite thickness bounded by two mathematical planes. We make, however, little mention of this method, since it seems to be of only minor importance in connec­ tion with the statistical treatment of an interface. To avoid any ambiguity, the treatment of a spherical interface given in this article is based not on the original method of GIBBS but on the method modified by HILL [8J and KONDO [9]. This method, however, is not applicable to non­ spherical interfaces, which will not be dealt with in this article. Although all the relations for a plane interface can be deduced from the cor­ responding ones for a spherical interface by putting the curvature equal to zero, the planar and the spherical cases are considered separately because of the prac­ tical importance and easy physical visualization of a plane interface.

Inhalt

The Structure of Liquids.- I. General nature of liquid structure.- a) Molecular constitution of liquids.- b) Liquid models.- c) Actual structure of liquids.- II. The quantitative description of liquid structure.- a) Distribution functions and their properties.- b) Molecular mechanics and liquid structure.- III. Structure of uniform liquids.- a) The radial distribution function.- b) Structure-dependent properties.- c) Structure in the surface zone.- IV. Structure of non-uniform liquids.- a) Effect of irreversible processes.- b) Deformation of structure by viscosity.- c) Theory of non-uniform liquids.- d) Kirkwood's theory of dissipative processes.- V. Structure of quantum liquids.- a) Liquid helium.- b) Quantum theory of structure.- Molecular Theory of Surface Tension in Liquids.- A. Thermodynamics and quasithermodynamics.- I. Thermodynamics.- a) Thermodynamic quantities of interface layer.- b) Plane interface.- c) Spherical interface.- II. Hydrostatic approach.- III. Quasithermodynamics.- IV. Application of thermodynamics of irreversible processes.- V. Empirical equations for temperature dependence of surface tension.- B. Statistical mechanics.- I. Statistical thermodynamic method.- a) Canonical ensemble.- b) Grand canonical ensemble.- II. Mechanical definition of surface tension.- III. Numerical calculations.- a) Pure liquid.- b) Electrolyte solution.- c) Gas adsorption on a solid surface.- IV. Quantum statistical mechanics.- C. Lattice theory approaches.- I. Pure liquids.- a) Free volume theory.- b) Hole theory.- II. Solutions of non-electrolytes.- a) Regular solutions.- b) Polymer solutions.- References.- The Theory of Capillarity.- A. General theory.- B. Applications.- General references.- Sachverzeichnis (Deutsch-Englisch).- Subject Index (English-German).