MAGNETIC-SUSCEPTIBILITY OF HG1-XFEXSE

The low field AC magnetic susceptibility of Hg1-xFexSe (x = 0.045, 0.0 70 and 0.095) has been measured in the temperature range 12-150 K. Our experimental data as well as those reported earlier are compared with the extended nearest-neighbour pair approximation calculations taking into account the long-range antiferromagnetic exchange interaction be tween Fe2+ ions in the form J(R) = J(NN)/R-n. Good agreement is found between the theory and experiment with 11 K less than or equal to \J(N N)\ less than or equal to 15 K and n = 5.