The pressure effect on the enhanced itinerant paramagnetism of Ni₃Al and TiCo compounds

The pressure effect on the magnetic susceptibility of Ni₃Al and TiCo compounds is studied in the temperature range 20-293 K. The obtained magnetovolume effect values dln chi /dlnV and results of detailed theoretical calculations of density of states at the Fermi level as a function of the lattice constant were used to evaluate volume derivatives of the electron-electron interaction parameter J: dlnJ/dlnV=-0.9+or-0.15 (Ni₃Al) and -0.95+or-0.15 (TiCo). These results are compared with theoretical estimates of dlnJ/dlnV from ab initio LMTO band structure calculations.