Effect of Pressure on the Curie Temperature of ZrZn2

Abstract

The initial pressure derivative of the Curie temperature of Zr${\mathrm{Zn}}_{2}$ has been measured under hydrostatic conditions, yielding a value of - (1.95\ifmmode\pm\else\textpm\fi{}0.1)\ifmmode^\circ\else\textdegree\fi{}K ${\mathrm{kbar}}^{\ensuremath{-}1}$ for a sample with a Curie temperature of (21.5\ifmmode\pm\else\textpm\fi{}0.5)\ifmmode^\circ\else\textdegree\fi{}K. This is in good agreement with the values of -1.8 and -2.4\ifmmode^\circ\else\textdegree\fi{}K ${\mathrm{kbar}}^{\ensuremath{-}1}$ predicted by Wohlfarth using the model of a very weak itinerant ferromagnet and two different methods of calculation. The present measurement allows an estimate of the effective degeneracy temperature for Zr${\mathrm{Zn}}_{2}$ of 300\ifmmode^\circ\else\textdegree\fi{}K and an estimate for the initial differential susceptibility of 6.2\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}5}$ emu ${\mathrm{g}}^{\ensuremath{-}1}$ ${\mathrm{Oe}}^{\ensuremath{-}1}$.