# Problem With solving the Eigenvalues of Tight Binding Method

1. May 8, 2015

### omaralrawi

Dear All, this is my first post on this forum and hopefully I can get what I want. .
I am trying to build the band structure of graphene using the tight-binding method based on slater-koster correction. I use a special code to construct both Hamiltonian and overlapping matrix. I have seen when I try to diagonalize the final matrix to find the eigenvalues, the eight eigenvalues are same even if I move from Gamma- K - M. I presume there is a reason for that I don't understand it. So please I need your help to solve my issue.

2. May 13, 2015