Solid solution hardening and atomic displacement parameters in La1−xCexB6 crystals

Abstract The variation of the atomic displacement parameters with composition in La 1−x Ce x B 6 crystals was determined using single crystal X-ray diffraction data. Considerable reduction in these parameters was observed at Ce concentration x=0.32, indicating general lattice stiffening. These results correlate with the maximum value of microhardness measured on the (100) face at this composition. The “critical” concentrations of Ce and La atoms in La 1−x Ce x B 6 are related to the site percolation concentration p c ≽0.28 for simple cubic lattice.