b The surface energies [3] were computed employing the software TribChem. Further details on its features can be found in Ref. [4]. TribChem is an evolution of Triboflow and the density functional theory calculations were performed using VASP. The optimal number of layers are obtained by converging the surface energy according to the Fiorentini Methfessel procedure proposed in Ref. [5]. Namely, for increasing number of layers N, surface energies are extracted, and converged, from the linear fit of the relation Eslab (N)=2 A γ + N Ebulk, where Eslab is the N-layer slab total energy, Ebulk is the total energy of the bulk (calculated using the same 2D cell used for the surface calculation), and A is the slab unit cell area.
References:
[1] P. Restuccia, G. Levita, M. Wolloch, G. Losi, G. Fatti, M. Ferrario, M.C. Righi, Ideal adhesive and shear strengths of solid interfaces: A high throughput ab initio approach, Computational Materials Science 154 517 (2018). DOI: 10.1016/j.commatsci.2018.08.006.
[2] M. Wolloch, G. Losi, M. Ferrario, M. C. Righi, High-throughput screening of the static friction and ideal cleavage strength of solid interfaces, Scientific Reports 9, 17062 (2019). DOI: 10.1038/s41598-019-49907-2.
[3] P. Restuccia, G. Losi, O. Chehaimi, M. Marsili, and M. C. Righi, High-Throughput First-Principles Prediction of Interfacial Adhesion Energies in Metal-on-Metal Contacts ACS Appl. Mater. Interfaces 15, 19624 (2023). DOI: 10.1021/acsami.3c00662.
[4] G. Losi, O. Chehaimi, and M.C. Righi, TribChem: a Software for the First-principles, High-Throughput Study of Solid Interfaces and their Tribological properties, accpeted to Journal of Chemical Theory and Computation (2023). DOI: 10.48550/arXiv.2304.14367.
[5] V. Fiorentini, and M. Methfessel, Extracting convergent surface energies from slab calculations J. Phys.: Condens. Matter 8, 6525 (1996). DOI: 10.1088/0953-8984/8/36/005.