中文摘要：

根据量子化学理论,应用从头计算Hartree-Fock（HF）方法在6-31G（d）基组水平上对C20及硼、氮掺杂的C20进行几何构型全优化.比较了C20及硼、氮掺杂的C20的基态能量、能隙及结合能的大小.此外,还计算了掺杂分子的最强红外光谱及其对应的振动频率,并给出振动模式.结果表明：掺杂后,C19B和C18B2的能量升高了;与B原子相连的键的长度均增加;单位原子结合能的计算表明单原子掺杂要比双原子掺杂稳定,而硼掺杂要比氮掺杂稳定;前线轨道理论计算表明硼、氮掺杂后C20的能隙增大.

英文摘要：

The ground state of C20,the boron and nitrogen doping C20 are studied by applying the Hartree-Fock（HF） method.The ground state energy,energy gap and binding energy are calculated and compared between C20 and doping C20.The strongest infrared intensity and frequency are calculated and the corresponding vibration modes are distinguished additionally.It is found that the energies of C19B and C18B2 are enhanced and the bonds relatted with boron are enlarged.The calculation of binding energy reveals that the single atom doping C20 is more stable than the double atoms doping C20 and boron doping C20is more stable than nitrogen doping C20.Furthermore,it is found that the energy gap of C20 is increased after doping.