Electronic structure and x-ray photoelectron spectroscopy of wurtzite GaxAl1-xN solid alloy

Band energy structure of GaxAl1-xN solid alloy (x=0.15; 0.65) is calculated . All one-electron methods of band energy calculations (self-consistent nor m-conserving pseudo-potential (NCPP), linear muffin tin orbital method (LMT O) and linear combination atomic orbital (LCAO)) methods give considerable disagreement with the experimental data. We demonstrate that better agreeme nt with experiment is achieved when the NCPP wavefunctions are orthogonalis ed to the core-like states. Simultaneously additional geometry optimization improve the agreement with the optical data. We have carried out theoretic al and experimental investigation of the band density of states for two rep resentatives of the investigated wurtzite Ga(x)A(1-x)N solid alloys (with x =0.15 and 0.65).