Effects of unrestrained length on the buckling behavior of platinum nanowires: a molecular dynamics study

This paper presents a molecular dynamics (MD) simulation of a solid fcc platinum nanowire, subjected to uniaxial compression. The many-body, Sutton-Chen interatomic pair functional was used for this simulation. The velocity-Verlet algorithm was employed to determine the atomic positions and velocities during compressive deformation of the simulation cell. The system temperature was set at 300 K, controlled by the loose-coupling Berendsen thermostat. Four platinum nanowires with a circular cross-section of approximate diameter 1.4 nm was simulated, with unrestrained lengths of 2.94 nm, 6.08 nm, 12.35 nm and 15.09 nm. Internal dislocation was observed for lengths of 2.94 nm and 6.08 nm, where additional atomic layers were formed in the lateral direction, resulting in a transformation of the nanowire to a stable diamond-shaped cross-section. Out-of-plane buckling was observed for the longer lengths of 12.35 nm and 15.09 nm, with significantly smaller compressive strengths as compared to the shorter length nanowires.