Critical behavior in the Ising antiferromagnet MnTe2

Symmetry considerations indicate that although MnTe2 has cubic symmetry, the antiferromagnetic transition in this compound is Ising-like. Critical properties of MnTe2 have been studied in the reduced temperature range 5 x 10-4 < or = Vertical Bar t Vertical Bar = Vertical Bar (T-T/sub N/) / T/sub N/Vertical Bar < or = 1 x 10-1 by neutron scattering techniques. It is found that the critical exponent β = 0.431 +- 0.009 is anomalously large, while the value of ν = 0.635 +- 0.014 is in reasonable agreement with the expected theoretical estimates. The exponents can be reconciled with the theoretical values by application of corrections to scaling. However, the size of some of the corrections and the increased uncertainties in the exponents produced by the introduction of additional fitting parameters, make it difficult to be sure the analysis is justified