CHAINS COMPOSED OF NANOSIZE METAL PARTICLES AND IDENTIFYING THE FACTORS DRIVING THEIR FORMATION

In an attempt to identify the driving force for the formation of chain s composed of nanometer size Fe alloy particles that were recently rep orted, experiments have been carried out with the magnetic metals Fe, Co, and Ni and a nonmagnetic metal Cu. The samples obtained by a reduc tion of aqueous metal chloride solutions with potassium borohydride ha ve been characterized by x-ray diffraction, transmission electron micr oscopy, and superconducting quantum interference device magnetometer m easurements. The results reveal that the magnetic interaction between the adjacent particles plays a determining role in the chain structure formation. Although both crystallinity and boron content do not play a direct role, they influence significantly the magnetic properties, a nd thereby have an indirect role in the formation of the chain structu res. (C) 1997 American Institute of Physics.