Electrical resistivity measurement on the rare earth metal praseodymium under high pressure up to 32 GPa

Abstract

The rare earth metal praseodymium (Pr) transforms from the d-FCC crystal structure (Pr-III) to the α -U type one (Pr-IV) at 20 GPa with a large volume collapse ( Δ V / V = 0.16 ). It has been considered that the 4f electrons in Pr ion change from the localized to itinerant states across the transition. In order to investigate the electronic state of the phase IV, we performed the high pressure electrical resistivity measurement using the diamond anvil cell (DAC) up to 32 GPa. In the Pr-IV phase, the resistivity shows an upward curvature, which suggests the narrow energy band of the itinerant 4f electrons near Fermi energy. At higher temperature side of the Pr-IV phase, the resistivity shows a small hump-like anomaly at T 0 .