[en] The molar heat capacity at constant pressure of LiInS₂, LiInSe₂ and LiInTe₂ was measured in the temperature range from about 200 K to 550 K. An analysis of the experimental data showed that the anharmonic contribution to the heat capacity can be described by a polynomial of fourth order in the temperature. A comparison of the results for the LiInC₂/sup VI/ compounds with those for the AgB/sup III/C₂/sup VI/ and A/sup II/B/sup IV/C₂/sup V/ chalcopyrite compounds showed that the lattice anharmonicity effects are essentially influenced by the specific nature of the Li-C/sup VI/ bond. (author)