Strong Coupling of Magnetism and Lattice Induces Near-Zero Thermal Expansion over Broad Temperature Windows in ErFe10V2-xMox Compounds

Alloys with low thermal expansion could overcome thermal stress issues under temperature-fluctuated conditions and possess important application prospects, while they are restricted to finite chemical components and temperature windows. In this study, we report a novel class of near-zero thermal expansion (near ZTE) alloys, ErFe10V2-xMox, over a wide temperature range (120-440 K). Neutron diffraction and magnetic measurements demonstrated that the ErFe10V2-xMox compounds exhibited complex ferrimagnetic (FIM) structures below Curie temperature (TC). The near-ZTE behaviors were closely related to the itinerant Fe 3d moments in the collinear FIM states, as well as the geometric [-Fe-Fe-] linkages. Further, X-ray absorption near-edge structure (XANES) spectra revealed that the nonmagnetic substitution changed the electronic valence states of Fe atoms, which, in turn, changed Fe 3d moments and T-C, hence, regulating the thermal expansion behaviors. Our work provides an insight into chemical modifications of thermal expansion in magnetic intermetallic compounds.

Automated summary

A novel class of near-zero thermal expansion alloys, ErFe10V2-xMox, demonstrated unique properties over a wide temperature range. The thermal expansion behavior of the alloys is closely related to their structure and electronic valence states.