Structural phase transition in the superconducting pyrochlore oxide Cd2Re2O7 Original Research Article

We report a structural phase transition found at in a pyrochlore oxide Cd2Re2O7 which shows superconductivity at X-ray diffraction experiments indicate that the phase transition is of the second-order, from a high-temperature phase with the ideal cubic pyrochlore structure (space group ) to a low-temperature phase with another cubic structure (space group ). It is accompanied by a dramatic change in the resistivity and magnetic susceptibility and thus must induce a significant change in the electronic structure of Cd2Re2O7.