Pressure-induced structural phase transition in NdAl x Ga 2−x

摘要: High-pressure neutron-diffraction experiments on the pseudo-ternary compound NdAlxGa2-x revealed a pressure-induced isostructural phase transition for x=1.00 and 1.08 above about 1.5 GPa at room temperature. Within its hexagonal AlB2 structure changes lattice ratio c/a discontinuously from 0.97 to 0.84 in analogy chemical pressure x>1.12. Pressures up 5.2 did not result pure high-pressure but rather mixture of both phases. The intermetallic MN2 phases are known appear two distinct groups with different ratios. observed is discussed within framework near-neighbor diagrams.