Magnetic Study of the Manganous Sulfates MnSO4 and MnSO4·H2O

Autor: J. P. Krebs, J. de Gunzbourg, Y. Allain
Rok vydání: 1968
Předmět:
Zdroj: Journal of Applied Physics. 39:1124-1125
ISSN: 1089-7550
0021-8979
Popis: The magnetization measurements up to 420 kOe made on antiferromagnetic powder specimens of MnSO4 and MnSO4·H2O between 1.6° and 70°K have revealed saturation fields of 250 and 320 kOe, respectively. The saturation value of the magnetization is in good agreement with the theoretical value for Mn2+(5 μB). The moment before saturation does not vary linearly with the applied field. This fact could be explained by spin‐wave theory or by a biquadratic term in the exchange energy. The anisotropy and the exchange fields have also been estimated from our experiments. The susceptibility versus T plot has given the Neel temperature TN and the effective moment which corresponds to the S state of Mn2+.Specific heat measurements have also been accomplished on MnSO4. They confirm our value for TN (11.5°K) and show three other peaks below the Neel temperature, two of which could correspond to the transitions theoretically forseen for this magnetic structure (cycloidal cone spiral) by Solyom.
Databáze: OpenAIRE