Computer simulation of thin nickel films on single-layer graphene

The energy, mechanical, and transport properties of nickel films on a single-layer graphene sheet in the temperature range 300 K $\le T\le$ 3300 K have been investigated using the molecular dynamics method. The stresses generated in the plane of the metallic film are significantly enhanced upon deposition of another nickel film on the reverse side of the graphene sheet. In this case, the self-diffusion coefficient in the film plane above 1800 K, in contrast, decreases. An appreciable temperature elongation per unit length of the film also occurs above 1800 K and dominates in the “zigzag” direction of the graphene sheet. The vibrational spectra of the nickel films on single-layer graphene for horizontal and vertical displacements of the Ni atoms have very different shapes.