Activation Energy of Cation Migration in Titanomagnetites

Autor: Creer, K. M., Ibbetson, Jill, Drew, W.
Zdroj: Geophysical Journal International; January 1970, Vol. 19 Issue: 1 p93-93, 1p
Abstrakt: Some basalts from the Azores Islands, containing homogeneous titano-magnetites, exhibit a rapid increase in magnetization when heated in air to about 400 °C. A new magnetic phase with a Curie point of about 540 °C is produced. By measuring the rate of increase in magnetization at different temperatures the activation energy of the chemical change involved has been calculated to be 0.5 eV per molecule, and it is suggested that this corresponds to migration of cations in the spinel lattice.
Databáze: Supplemental Index