Effects of bispherical nanopore concavo-convex walls on fluid structure, tangential and normal pressure components, and the validity of well-established bulk regularities; a DFT approach

Abstract

The modified fundamental measure theory is employed to investigate the effects of wall curvature and wall-fluid interactions on the structure tangential and normal pressure of fluids confined in bispherical nanopores. Results show that the values for density and tangential pressure at the concave wall of hard bispherical pores are larger than those at the convex wall. Opposite results are obtained when a strong attraction potential is applied to the convex wall while the concave wall is a hard one. It is possible to get symmetrical profiles of density and tangential pressures with respect to two walls of a pore by varying the curvature and wall-fluid interactions. Although these two factors drastically affect the local density, pressures, and their average values, the behavior of the average values of their thermodynamic properties does not depend on them. This indicates that certain well-established bulk regularities are valid for fluids confined in bispherical pores.