Electron microscopy and ⁵⁷Fe Mössbauer spectra of 10 nm particles, intermediate in composition between Fe₃O₄and γ‐Fe₂O₃, produced by bacteria

Abstract

An analysis was made of magnetic 10 nm particles produced by bacteria under anaerobic conditions in an aqueous liquid. By means of transmission electron microscopy, applying electron diffraction, the particles were found to consist of Fe 3 O 4 (magnetite) or γ‐Fe 2 O 3 (maghemite). Low temperature 57 Fe Mössbauer spectra showed the particles to consist probably of an intermediate solid solution between both compounds.