Average and Local Crystal Structures of (Ga1–xZnx)(N1–xOx) Solid Solution Nanoparticles...

We report the comprehensive study of the crystal structure of (Ga1􀀀xZnx)(N1􀀀xOx) solid solution
nanoparticles by means of neutron and synchrotron x-ray scattering. In our study we used four
different types of (Ga1􀀀xZnx)(N1􀀀xOx) nanoparticles, with diameters of 10 - 27 nm and x = 0.075
- 0.51, which show the narrow energy-band gaps from 2.21 to 2.61 eV. The Rietveld analysis of the
neutron diffraction data revealed that the average crystal structure is the hexagonal wurtzite (space
group P63mc), in agreement with previous reports on similar bulk materials. The pair-distribution
function (PDF) analysis of the same data found that the local structure is more disordered than the
average one. It is best described by the model with a lower symmetry space group P1, where atoms
are qusirandomly distorted from their nominal positions in the hexagonal wurtzite lattice.