摘要
以内部掺杂1对硼氮原子的单层锯齿形边缘石墨烯为模型,利用密度泛函理论B3LYP/6-31G(d,p)方法优化模型的结构.定义硼氮双原子掺杂石墨烯体系中各位点的ABEEMσπ标号,以HF/STO-3G方法计算的体系电荷为标准,拟合并确定所定义标号的ABEEMσπ参数.应用其计算硼氮双原子掺杂石墨烯的电荷分布并与从头算计算结果作对比,结果显示用ABEEMσπ方法算出的电荷与从头算方法算出的电荷具有很好的一致性.使用前线分子轨道理论分析其最高占据轨道(HOMO)和最低空轨道(LUMO),且比较能隙值的变化.可以得出,石墨烯中参与导电的电子主要分布在上下锯齿形边缘,内部掺杂1对硼氮原子后,它的HOMO和LUMO基本不变,不影响其导电性.态密度图显示了掺杂1对硼氮原子后,虽然在部分能量范围内,石墨烯的分子轨道态密度变化明显,但在HOMO和LUMO处的态密度基本不变,Fermi能级的位置也不变,因此能隙不变.通过比较掺杂前后石墨烯的分子轨道态密度图,更能直观地得出石墨烯的导电性不发生变化.
The zigzag-edge graphene doped with boron（B）and nitrogen（N）atoms is used as the model,it should be optimized by B3LYP/6-31G（d,p）method.We define the ABEEMσπlabels of its atoms and bonds.After the ABEEMσπparameters are determined,the charges calculated by ABEEMσπmethod are compared with those obtained by HF/STO-3G method.The results show that they are consistent.Through the frontier molecular orbital theory,the HOMO and LUMO are analyzed.The results show that electrons participate in conducting of the graphene are mainly distributed in the upper and lower edges.The HOMO and LUMO of graphene remain unchange after doping with B and N atoms,the conductivity is unaffected.The DOS fig shows that there is an effect on DOS after doping with B and N atoms,but the DOS of HOMO and LUMO are not changed.The position of Fermi level is unchanged,so it does not change the energy gap of graphene.By comparing the DOS of graphene,it can be more intuitive to reflect that the conductivity is unaffected after doping with B and N atoms.
出处
《辽宁师范大学学报（自然科学版）》
CAS
2015年第3期337-343,共7页
Journal of Liaoning Normal University:Natural Science Edition
基金
国家自然科学基金项目(21473083
21133005)
