The magnetic-non magnetic transition of cerium impurities in lanthanum-thorium based alloys

A simple theoretical model which assumes a linear increase with thorium concentration for the cerium 4? level with respect to the Fermi level can explain both the decrease $\text{ΔT}{}_{\mathrm{c}}\text{c}$ of the superconducting temperature and the logarithmic slope $\text{d}\text{ρ}\text{c}\text{dln}\text{T}$ of the Kondo resistivity in LaTh based alloys with cerium impurities. The model yields two different maxima for |$\text{d}\text{ρ}\text{c}\text{dln}\text{T}$| and $\text{ΔT}{}_{\mathrm{c}}\text{c}$, the second one of which occurs when the resistivity minimum disappears, in very good agreement with experimental data.