69Ga NMR in Pu1−xGax (x < 0.01) alloy

69Ga nuclear magnetic resonance (NMR) experiments have been carried out on the Pu0.995Ga0.005 alloy at temperatures between 20 and 420 K at magnetic field of 9.4 T to study the local charge symmetry and magnetic behavior of the Pu atoms surrounding solute Ga. In accordance with optical metallography and X-ray diffraction studies the investigated plates of alloy (20 mm × 3 mm × 0.2 mm) represent at room temperature the single α-phase material without any detectable macroscopic segregation of other phases (the corresponding volume fraction <0.03). It was revealed that the magnetic shift of the 69Ga NMR central line and the electric quadrupole broadening of the Ga NMR spectrum trace temperature dependence of the NMR parameters is observed for the δ-phase plutonium alloy Pu0.95Ga0.05. On the basis of 69Ga NMR and X-ray data obtained, it is suggested that specific microscopic areas with a size less than 100 nm exist in the α-phase plutonium alloys Pu0.995Ga0.005. The local charge and magnetic environment of the solute Ga in these microscopic areas are similar to the observed in the stabilized δ-Pu alloy.