Antiferromagnetic Resonance in MnTiO3

The effective internal field (2H_EH_A)^½ as well as its temperature dependence has been found from antiferromagnetic resonance experiments for two different single crystals of MnTiO₃, and from absorption edge data for a pure powder sample. The data are consistent with a uniaxial collinear two sublattice model as predicted from dc susceptibility and neutron diffraction measurements. The data for one crystal yielded results in good agreement with the powder material with a g value of 2.1 and effective internal field of 52 kgauss at 4.2°K. All samples followed a Brillouin function for spin $\frac{5}{2}$ fairly well but with different Néel temperatures higher than that previously reported for this material.