Ab initio study of nitrogen and boron doped dimers

The first principle calculations have been employed to study the structural, electronic and magnetic properties of gold contacted C60 dimers that are substitutionally doped with boron and nitrogen atoms. Doping of C60 dimers causes size changes, symmetry distortions, induced magnetism and the emergence of states above the Fermi level. Hybridisation of the molecular orbitals of the doped C60 dimers with the states of the monoatomic gold chains leads to level broadening and significant changes in the spin-polarised densities of states. The variations in the obtained total magnetic moments indicate that the considered complexes are highly favourable for further investigations as building blocks of magnetic nano devices. Transmission spectrum of BN doped complexes shows a significant variation with different levels of doping. The I–V characteristics display rectifying behaviour for a controlled amount of doping enabling the dimers to act as molecular rectifiers.

本研究采用第一性原理计算，对经硼、氮原子取代掺杂的金接触C₆₀二聚体的结构、电子及磁学性质展开了系统探究。对C₆₀二聚体进行掺杂会引发尺寸变化、对称性畸变、诱导磁性，以及费米能级之上新电子态的出现。掺杂C₆₀二聚体的分子轨道与单原子金链的电子态发生杂化，将导致能级展宽与自旋极化态密度的显著改变。所获得的总磁矩变化表明，本次研究的这类复合物作为磁性纳米器件的构筑基元，具备极高的后续研究价值。硼氮掺杂复合物的传输谱随掺杂浓度的不同呈现出显著差异。在可控掺杂量下，该复合物的电流-电压特性表现出整流行为，可使二聚体充当分子整流器。