Mössbauer and X-Ray Study of MnTe2

Experiments on the Mössbauer effect of 125 Te and the X-ray diffraction for antiferromagnetic MnTe 2 were performed. Temperature dependence of the spin direction has been observed for a magnetic ordering of the first kind fcc lattice. The angle between the spin direction of Mn and the principal axis of electric field gradient increases from 23° at 4.2 K to 30° at 60 K and decreases to 0° at 70 K. Discontinuous changes are found in hyperfine field and quadrupole splitting at 60 K. An analysis of X-ray diffraction intensities for (742), (732) and (721) reflections shows that u parameter increases by 0.0015 at 60 K as temperature decreases and that Einstein temperature increases from 95 K to 105 K below 60 K. The crystallographic phase diagram of MnTe–Te system is given.