Low-temperature stable nanometer-size fcc-Fe particles with no magnetic ordering

Nanometer-size Fe particles ( approx 8 nm diameter) with the face-centered-cubic (fcc) structure were made using a technique based on the transversely excited atmospheric CO sub 2 -laser-induced breakdown of Fe(CO) sub 5 . This fcc gamma -Fe phase is extremely stable based on observations over three years. Mossbauer spectra over a small velocity range with and without a magnetic field applied show that these nanometer fcc-Fe particles are paramagnets down to a temperature of 1.8K. This result supports theoretical predictions that the ground state of fcc Fe depends strongly on the volume.