Heat capacity measurements on irradiated and non-irradiated Mo3Ge and Mo5Ge3

We have measured the heat capacity of irradiated and non-irradiated Mo₃Ge and Mo₅Ge₃ in the temperature range ≈ 1.6 to 10 K. An irradiation of 2.2 × 10¹⁹ neutrons cm^-2 results in an increase in the superconducting transition temperature T_c from < 1.6 K in the non-irradiated state to ～ 4 K after irradiation for Mo₃Ge and a corresponding change from < 1.6 K to ～ 3 K for Mo₅Ge₃. Our analysis shows that this change in T_c is not accompanied by a change in the electronic density of states (within experimental error) but rather a decrease in the Debye temperature from 392 to 322 K for Mo₃Ge and 377 to 320 K for Mo₅Ge₃.