Disjoining pressure for non-uniform thin films

B. Dai bing@cut.this.part.lanl.gov

A. Redondo redondo@cut.this.part.lanl.gov

A. Graham graham@cut.this.part.lanl.gov

G. Leal lgl20@cut.this.part.engineering.ucsb.edu

It is known that the concept of the disjoining pressure between two parallel interfaces due to van der Waals interactions cannot generally be extended to films of nonuniform thickness. We derive a formula for the disjoining pressure for a film of non-uniform thickness by minimizing the total Helmholtz free energy for a thin film residing on a solid substrate.