Electrical resistance of nickel in the range 300–725 K and 0–2 GPa

Abstract

The electrical resistance R of Ni has been measured as a function of temperature T and pressure p over the range 300–725 K and 0–2 GPa (0–20 kbar). In contrast to recent reports, we see no anomalies in R(p) at 300 K, and we see no change in sign in dR/dp at the Curie temperature $T_C$. The pressure coefficient of R was -1.82×${10}^{\mathrm{-}2}$ ${\mathrm{GPa}}^{\mathrm{-}1}$ at 300 K, increasing with T to a peak value of -2.5×${10}^{\mathrm{-}2}$ ${\mathrm{GPa}}^{\mathrm{-}1}$ at $T_C$, above which it rapidly decreased to a value 20% below the room-temperature value. The data are analyzed using simple models; the resistivity at constant volume is found to deviate significantly from the constant-p data above $T_C$ and a small anomaly is detected in d(lnR)/dp that could possibly be an effect of band-structure changes at $T_C$.