运用密度泛函理论的PW91/DNP方法对C(6,0)@BN(n,0)体系的结构与稳定性进行了研究,发现最适合与C(6,0)纳米管形成的嵌套体系的锯齿型BN纳米管是BN(15,0)和BN(16,0),在形成的C(6,0)@BN(15,0)和C(6,0)@BN(16,0)中,碳壁与氮化硼壁之间的距离分别为0.36和0.40nm.在最稳定的C(6,0)@BN(16,0)体系中,发现内层碳纳米管的电子结构并未受到外层氮化硼纳米管的影响,然而氮化硼纳米管的能隙缩小了0.5eV.对C(6,0)@BN(16,0)的轨道分析表明,碳纳米管与氮化硼纳米管之间的作用力为范德华力。
The geometry and electronic structure of C(6,0)@BN(n,0) system were studied by density functional theory method with DMol3 code. It was found that the favorable BN(n,0) nanotubes for C(6,0) to form C(6,0)@BN(n,0) were BN(15,0), and BN(16,0) nanotubes. In C(6,0)@BN(15,0) and C(6,0)@BN(16,0), the interwaU distances between the inner C tube and outer BN tube were 0.36 and 0.40 nm, respectively. In the most stable C(6,0)@BN(16,0), the conductivity of C nanotube was not affected by outer BN tube while the bandgap of BN nanotube was reduced about 0.5 eV. The analysis of orbitals of C(6,0)@BN(16,0) indicated that the interaction between C and BN nanotube was typical van der Waals interaction.