Specific heat of the degenerate Kondo model: Exact results in the presence of crystal fields

The infinite set of coupled, nonlinear integral equations describing the thermodynamics of the Coqblin-Schrieffer model in the presence of crystal fields is investigated for the cases of a quartet split into two doublets and a j=(5/2 multiplet split into three equally spaced doublets. The zero-temperature limit is treated analytically, while for finite temperatures a special numerical algorithm is developed to treat the crystal-field boundary conditions that are required for the solution of the integral equations. The results for the specific heat are discussed and compared with experiments on ${\mathrm{Ce}}_{\mathrm{x}}$ ${\mathrm{La}}_{1\mathrm{-}\mathrm{x}}$ ${\mathrm{B}}_6$ and ${\mathrm{CeAl}}_3$.