Three-dimensional aspect of the surface tension: An approach based on the total pressure tensor

The conditions of mechanical equilibrium were considered, and the generaliz ed notion of the surface tension at an arbitrarily curved surface layer was analyzed on the basis of the total nondiagonal pressure tensor including t he external fields and anisotropic even in the bulk phases. It was shown th at the transverse surface tension can be eliminated using the selection of a dividing surface; however, in the general case. this surface does not exh ibit the properties of the tension surface. On the whole, three-dimensional and nondiagonal character of the tensors of excess surface stresses determ ined by the integration over the volume and the cross section of the surfac e layer is retained at any selection of the dividing surface.