# extracting parameters from .SKF files ,

I have a question about interpreting .SKF files, I am using these parameters to model defective graphene,

when I use parameter set given by dftbBaby/C-C (I think this is from Hotbit) or the parameter set given by the following paper:

Porezag, D., Frauenheim, T., Köhler, T., Seifert, G., & Kaschner, R. (1995). Construction of tight-binding-like potentials on the basis of density-functional theory: Application to carbon. Physical Review B, 51(19), 12947.

(both of which give approximately $$H_{pp\pi} ~ -3 eV$$ at ~1.4 Angstrom) then after performing slater-koster transformations and embedding the H0 and S values into the secular equation, I get the correct band structure.

however, for other parameterizations, for example say dftb/mio, the value I get for $$H_{pp\pi}$$ from interpolation of hopping integrals is much smaller ~ 2eV and gives wrong band structure:

here for sure it is me who is doing sth wrong because using the same parameter set DFTB+ gives the correct band structure,

I am not sure whether I am not interpreting the SKF files properly (in a naive attempt the band structure can be corrected by increasing the value of r0 given in the SKF file which is equal to shifting the curves downwards) or is there any other step I need to perform before embedding the H and S values into the secular equation ?

I figured that I was using the wrong format, the detailed format of .SKF files is given here

The correct extracted parameterization profile is given below: