The cubic NaZn₁₃-type La(Fe_1-xCo_x)_11.4Al_1.6 compounds were synthesized and extensively explored through crystal structure and magnetization analyses. By optimizing the chemical composition, the isotropic abnormal properties of excellent zero and giant negative thermal expansion in a pure form were both found at different temperature ranges through room temperature. Moreover, the temperature regions with the remarkable abnormal thermal expansion (ATE) properties have been broadened which are controlled by the dM/dT. The present study demonstrates that the ATE behavior mainly depends on the special structural and magnetic properties. These diverse properties suggest the high potential of La(Fe_1-xCo_x)_11.4Al_1.6 for the development of abnormal expansion materials.

Physical Chemistry Chemical Physics, 2016