M@C_(20)H_(20)(M=Sc,V,Cr,Mn,Fe,Co,Ni)几何结构和电子性质的理论研究  

Theoretical studies on the geometric and electronic properties of M@C_(20)H_(20)(M = Sc,V,Cr,Mn,Fe,Co,Ni)

作　　者：曹青松[1,2] 刘玉真[2] 邓开明[2] 

机构地区：[1]南京理工大学泰州科技学院,泰州225300 [2]南京理工大学应用物理系,南京210094

出　　处：《原子与分子物理学报》2016年第3期457-462,共6页Journal of Atomic and Molecular Physics

基　　金：国家自然科学基金(21403111)

摘　　要：采用密度泛函理论(DFT)中的广义梯度近似(GGA)方法对M@C_(20)H_(20)(M=Sc,V,Cr,Mn,Fe,Co,Ni)几何结构和电子性质进行了计算研究.几何结构优化发现,过渡金属原子M内掺到C_(20)H_(20)笼时,都稳定于碳笼中心.能隙和内掺能计算发现,M@C_(20)H_(20)的热力学稳定性随着M原子序数的增大而逐渐减弱,内掺M原子使得其动力学稳定性大幅度下降,但是其中Ni@C_(20)H_(20)结构仍然具有良好的热力学和动力学稳定性,其有望在实验中被成功合成出来.电子性质研究发现,随着M原子序数的逐渐增大,M原子对M@C_(20)H_(20)前线轨道的贡献也越来越大,M@C_(20)H_(20)(M=Sc,V,Cr,Mn,Fe,Co)都具有一定的磁矩,而Ni@C_(20)H_(20)为闭壳层结构,磁矩为零.The generalized gradient approximation （GGA） based on density functional theory （DFT） was used to analyze the geometric and electronic properties of the endohedral fullerene M@C20H20 （M=Sc, V, Cr, Mn, Fe, Co, Ni）. The geometric optimization shows that the M atom is all stable in the center of the cages. Energy gap and the doping energy calculations indicate that the thermodynamic stability of M@C20H20 decreases gradually with the increase of the atomic number of the M. The doped M atoms lead to the kinetic stability of the M@C20H20decreases greatly, but the Ni@C20H20 still has good both kinetic and dynamic stability, which is expected to be synthesized experimentally. The electronic properties demonstrate that The M atoms contribute to the frontier orbitals of M@C20H20 with increasing the atomic number of M. M@C20H20 （M=Sc, V, Cr, Mn, Fe, Co）, and allof them have magnetic moments, but Ni@C20H20 is nonmagnetic with a closed shell electronic structure.

关 键 词：富勒烯 几何结构 电子结构 密度泛函理论 

分 类 号：O641[理学—物理化学]