Induced Magnetic Properties of BN Nanotubes by the Adsorption of First-row Adatoms : An ab initio Study

This work is performed to study the effect of adsorption of various first row adatoms (such as Be, C, F, Li and O) on (8, 0) zigzag boron nitride nanotubes (BNNTs) on their structural, electronic and magnetic properties. These calculations are based on density functional theory using pseudopotentials technique. For this purpose, five different sites namely axial, hexagonal, zigzag, on top of N and/or B (which are the most preferred available sites for adatoms on (8, 0) BNNTs) were utilized. The energetically stable sites for each of the first-row adatoms are found to be different because of their different electronic configurations caused by the charge transfer/ rearrangements between s-p or p-p orbitals. The binding energies of all adatoms on (8, 0) BNNTs have been calculated through structural optimization process after adsorbing these five adatoms at the above said sites on the BNNTs and are found to be in the energy range from -2.04 to 2.96 eV. It is further elaborated that F, Be and C adatoms on (8, 0) BNNTs show strong induced magnetization at specific localized sites depending upon the nature of adatom, whereas weak magnetization is noticed for Li and O adatoms on the BNNTs. Such localized induced magnetization could be associated with the hybridization of s-p or p-p orbitals of adatoms and B and/or N atoms.