Heat capacity of magnetite in the range 0.3 to 10 K

Abstract

Heat-capacity measurements are reported for ${\mathrm{Fe}}_{3(1\mathrm{\ensuremath{-}}\mathrm{\ensuremath{\delta}})}$${\mathrm{O}}_{4}$ samples with \ensuremath{\delta}=0 and 0.0049 in the range 0.3 to 10 K. Differences in the heat-capacity curves are discussed. The Debye temperatures are 539 and 511 K, respectively; the corresponding exchange integrals as evaluated from Kouvel's model are ${J}_{\mathrm{AB}}$=2.35 and 0.604 meV, respectively.