Electronic structure of Gd-based Laves-phase alloys

Ab initio electronic-structure calculations based on the linearized muffin-tin orbital method are reported for the ferromagnetic intermetallic alloys Gd(${\mathrm{Al}}_{1\mathrm{-}\mathit{x}}$${\mathit{M}}_{\mathit{x}}$${)}_2$ with various nonmagnetic dopants M and x=0, x=0.25. The results of the theory are compared to x-ray photoemission spectroscopy data and magnetic measurements. We find good agreement between experiment and theory for ground-state properties and for the shape of the spectra near the Fermi level. The measured lowering of the paramagnetic Curie temperature in Gd(${\mathrm{Al}}_{1\mathrm{-}\mathit{x}}$${\mathit{M}}_{\mathit{x}}$${)}_2$ for increasing dopant concentration x can be explained by a corresponding decrease of the density of states N(${\mathit{E}}_{\mathit{F}}$) at the Fermi level.