SUPERCONDUCTIVITY IN LACD2

Low temperature heat capacity and resistivity measurements indicated t hat LaCd2 is a low temperature superconductor (T-c=1.44 K). It is a co nventional weak-coupling superconductor with a coupling constant lambd a approximate to 0.47. The electronic specific heat coefficient gamma (8.0 mJ mol(-1) K-2) and Debye temperature Theta(D) (186 K) were deter mined from heat capacity data. The covalent bonding in LaCd2 is probab ly responsible for preventing the softening of the phonon spectrum, wh ich probably accounts for the low T-2 value. LaCd2 is the first superc onducting intermetallic compound that has the CeCd2-type structure. Ho wever, compared with the lanthanum Laves phase compound superconductor s, the structural difference may be insignificant in determining the s uperconducting properties.