TEMPERATURE-DEPENDENCE OF THE MAGNETIC-SUSCEPTIBILITY OF A CRSI2 SINGLE-CRYSTAL

A single crystal of CrSi2 was grown by a modified floating-zone refining technique, and its magnetic susceptibilities and Hall coefficients in the directions of both the a and c axes were measured over a temperature range from room temperature to 1000 K. The susceptibilities were constantly negative over the temperature range and possessed a minimum value at 770 K. The temperature dependence of the hole concentration estimated from observed data of the Hall measurement suggested that above 770 K the susceptibility is primarily dominated by the contribution from charge carriers. The chemical composition of the crystal was estimated at CrSi1.985 by quantitative chemical analysis. A theoretical curve of susceptibility was calculated by assuming that the excess Cr atoms act as Cr3+ ions in the crystal. The observed susceptibilities were in good agreement with the theoretical curve. It was concluded that the Cr atoms constituting a stoichiometric CrSi2 lattice are quadrivalent by reason of their negligibly small contribution to the susceptibility. © 1990 The American Physical Society.