Molecular Dynamics of Rupture Phenomenon in a Liquid Film on Nanowire Under Isothermal Condition

Abstract

Dynamics of nano-meter-scale liquid film on nanowire is investigated through classical molecular dynamics simulation. Liquid film of argon with 12-6 Lennard-Jones potential on the solid surface with harmonic potential breaks up into several droplets in a relaxation process to make the total surface energy smaller. Instability emerged on the liquid film, its propagation along the wire, and pinching off of the nano-film are discussed. Theoretical investigations on this problem in a macroscopic-scale system have indicated that a liquid film on the wire of radius R will break up into drops if the axial wavelength of the surface perturbation λ > 2πR. If λ < 2πR, the film is stable. On a microscopic-scale, a similar phenomenon to a macroscopic system occurs. We simulate the liquid film with thickness e0 ≅ 1.5 nm on the solid cylinder. In addition, effect of wettability on instability concerned is examined by changing L-J potential parameter εINT.