Comparison of electronic and magnetic properties of Fe, Co and Ni nanowires encapsulated in beryllium oxygen nanotubes.

Abstract: The structure, electronic and magnetic properties of transition metals M₉ (M=Fe, Co or Ni) nanowires encapsulated inside armchair (8,8) beryllium oxygen nanotube (BeONT) [M₉@(8,8)] have been investigated by first-principles calculations. Due to strong interaction between inner M₉ nanowire and outer BeONT, not only a near square cross-section shape is formed for outer BeONT but also a counter-clockwise rotation about their common axis takes place for the M₉ nanowire. The charge density accumulated strongly around the O atom implies a large charge transfer from Fe atom (as well as from Be atom) to O atom and thus the ionic-binding characters exist among them. The negative values of the binding energies for all three M₉@(8,8) hybrid systems indicate the combining processes of all three M₉@(8,8) hybrid systems are exothermic. Therefore, the stable insulator (8,8) BeONT can be used to shield the M₉ nanowire. Although (8,8) BeONT is non-magnetic and a decrease in the magnetic moments is found after M₉ nanowires are encapsulated inside (8,8) BeONT, less than ten percent reduction in the magnetic moments shows all three M₉@(8,8) hybrid systems can be utilized in spin transport devices. [ABSTRACT FROM AUTHOR]