First of all we need the “*.bas” file of the tip and sample geometry (separately). We can use the Jmol to view the “*.xyz” file. Tip should have tip apex at 0.0 0.0 xy position. We have even to prepare the “Fdata” of given properties of elements of tip and sample we will use. For followings we should run the fireball to relax these structures. If you are using new FIREBALL input format, set up followings at the “fireball.in” file:
‐ basisfile = <filename>
‐ lvsfile = <filename>
‐ kptpreference = <filename>
‐ nstepf = 1
Than you have the “CHARGES” of both the systems tip and sample
We need several files before we can simulate the STM scanning for both tip and sample. For sample it is “Atomo_i” with Hamiltonian of the surface and “struc.inp files” with the structure informatioon, hopping file “tip_sample_i_j.inp” (“interaction_i_j.dat”), “tip_e_str.inp” and “tip_g_str.inp” with the densities and geometry of the tip respectively.