question about atoms projected band structure

[Quhe]

I have tested the new function of band structure projected on atoms in ATK 12.8.b2, but found that the projected band structure cannot coincide with the band structure of the combined system.
For example, I calculated the band structure of the Al adsorbed graphene monolayer. The band structure projected on the Al atoms does't belong to that of  the combined system.

[Nordland]

I have redone the calculation, and it appears to be correct for me or at least I can't say anything that is wrong.

The projected bandstructure is the bandstructure of a sub-part of the system (that is the eigenvalues of a sub-matrix of Hamiltonian), and only if this is completely uncoupled from the rest of the system will the bandstructure coincide within the full bandstructure.

The stronger the coupling between the Al and the Graphene the larger difference will between in bandstructure.