Contribution to the potential energy of a single atom (represented by large red dot in the insert) as a function of distance z from the surface of three neighboring planes, separated also by distance z. The case of ABA and ABC ordering of planes is considered. The atom is considered in two positions with respect to the first plane, AA(1) or AB(1). The energy contribution from the third plane is exactly the same regardless whether it is the A plane or C plane. Energy from the second and third planes is rescaled 5 and 10 times, respectively. Classical L–J potential 12–6 with parameters ϵ=2.80 meV and σ=3.38 Å is used. The depth of the potential well for the lowest curve denoted as AB(1)+AA(2)+AB(3)+AA(4)+AB(5) (which shows the sum of energies from 5 consecutive planes in AB configuration) is 52 meV.