First-principles calculation for bowing parameter of wurtzite InxGa1 − xN

Numerical simulation based on first-principles calculation is applied to study the structural characteristics and band-energy properties of wurtzite InxGa1 − xN. The lattice constants a and c apparently deviate from the Vegard's law. The deviation parameter is 0.047 ± 0.011 Å for the a lattice constant, and −0.117 ± 0.026 Å for the c lattice constant. A band gap energy bowing parameter of 1.782 ± 0.076 eV is obtained with the equilibrium lattice constants, and 1.916 ± 0.068 eV is obtained with the lattice constants derived from the Vegard's law.