AbstractThe band structure in the high‐symmetry points of the TIGaSe2, Brillouin zone is calculated by the pseudopotential method. The top of the valence band is found to be located at the Γ point. The bottom of the conduction band is located at the line Γ–Y and the additional extremum of this band – at the point Γ of the Brillouin zone of TlGaSe2. The data obtained are compared with the results of previous band calculations and optical absorption data of