Derivation of a Force Field for Computer Simulations of Multi-Walled Nanotubes. II. Tungsten Diselenide

We propose a force field designed to model multi-walled WSe2 nanotubes whose size is beyond the capabilities of ab initio methods. The parameterization of interatomic potentials is successfully tested on single-walled and double-walled nanotubes, the structure of which is determined using non-empirical calculations. This force field has been used to model the structure and stability of chiral and achiral multi-walled WSe2 nanotubes with diameters approaching experimental values. The properties of WSe2-based nanotubes are compared with the properties of analogous WS2-based nanotubes calculated using the force field, which was published in the previous paper I of this series. The interwall distances obtained from the simulations are in good agreement with recent measurements of these parameters for existing WS2 and WSe2 nanotubes. It is found that the interwall interaction contributes to the stabilization of multi-walled nanotubes slightly more in the case of WSe2 than in the case of WS2. Analysis of the deviation of the nanotube shape from the cylindrical one showed a close similarity of the structure of the tubes of both compositions.