Temperature-Dependent Structural Behavior of Bi0.5Nd1.5Ru2O7

The structure of the Bi-doped pyrochlore, Bi0.5Nd1.5Ru2O7has been studied between 20 and 300 K using powder synchrotron diffraction methods. The structure shows an abupt change in the Bi(Nd)–O and Ru–O contacts near 200 K as a consequence of a metal–semiconductor transition. There is a marked hysteresis in the structural parameters upon rewarming the sample.