Magnetic properties of cubic and hexagonal chromium hydrides:: a comparison of the magnetic susceptibility with the 53Cr NMR Knight shift

We have measured the Cr-53 Knight shift in cubic and hexagonal chromium hydrides with atomic hydrogen-to-chromium ratio H/Cr approximate to1 in the temperature range 3-300 K. The shifts (0.30% in cubic phase, 0.53% in hexagonal phase) are temperature independent and imply that the intrinsic magnetic susceptibilities of the respective hydrides are also temperature independent. The values of intrinsic magnetic susceptibilities have been determined from the analysis of magnetisation isotherms recorded in the temperature range 1.7-300 K, and in magnetic field strengths up to 55 kOe. The isotherms indicate the presence of paramagnetic and ferromagnetic impurities in the samples, the magnetisation of which was subtracted from the measured magnetisation data. The cubic and hexagonal chromium hydrides are Pauli paramagnets with intrinsic susceptibilities of 5.9 10(-8) and 5.0.10(-8) m(3)/kg, respectively. (C) 2001 Elsevier Science B.V. All rights reserved.