# Nanosurf Lab

### Site Tools

sample_hamiltonian

# Differences

This shows you the differences between two versions of the page.

 sample_hamiltonian [2009/11/26 10:36]vroz sample_hamiltonian [2011/02/18 13:13] Line 1: Line 1: - \\ - ===== Sample Hamiltonian (Atomo_i, struc.inp files) ===== - - Once we have the “CHARGES” we can produce the "​Atomo_i"​ files by the - FIREBALL. “CHARGES” file has to be at the same directory when you are running - the FIREBALL. To the “fireball.in” we will write: - - __&​OPTION__ part - - ‐ nstepf = 1 \\ - ‐ ifixcharge = 1 \\ - - __&​OUTPUT__ part - - ‐ iwrtatom = 1 - - Than you obtained “Atomo_i” files and the “struc.inp” file, which should be - modified to work properly when you run the STM simulation. How to do that: - The “struc.inp” file contains some information about the sample: - - 1                                 ​!number. of atoms in unit cell \\ - 1                                 ​!initial and final atom which is contributing to the tunneling current \\ - 12                                ! number maximum of neighbours \\ - //!! you have to modify this upper part// - - 0.000000 0.000000 0.000000 1      ! coordinates and type of each atom \\ - . \\ - . \\ - . \\ - - //!! Next part (up to the lattice vectors) must be added// \\ - 4                                 ​!number of orbitals in each type of atom (in a row) \\ - 2                                 ​!number of shells of each atom type (in a row) \\ - 0 1                               !l of each shell type atom=1 (each atom type in a row) \\ - 16                                !nkprl: no. of k's in one row (nk=nkprl2),​ =0 read a samplek.kpts file \\ - 1 1                               ​!index_cell1,​ index_cell2 (ncell = (2*index_cell1+1)*(2*index_cell1+1) \\ - - 0.866025 , 0.5 , 0.               ​!Horizontal lattice vector (x‐axis) \\ - 0.866025 , ‐0.5 , 0.              !Horizontal lattice vector (y‐axis) \\ - //!! We have to delete the last row of Lattice vector// - - The fixing the "​nkprl"​ value to 0 and using the fireball k-points (with the - opposite to complete the Brouilloin) is strongly reccomended. - The "​index_cell1"​ and "​index_cell2"​ are relative to the number of cells we - need in each direction x and y to avoid the border problems. The product of them - gives us number of repetition unit which influence is involved to the - computation. - - \\