C_(80)H_(80)几何结构和电子性质的密度泛函研究  

Density functional study on the geometric and electronic properties of C_(80)H_(80)

作　　者：曹青松[1,2] 袁勇波[2] 肖传云[2] 陆瑞锋[2] 阚二军[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]南京理工大学理学院,南京210094

出　　处：《物理学报》2012年第10期312-317,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10974096;11004107)资助的课题~~

摘　　要：采用密度泛函理论方法中的广义梯度近似,对C_(80)H_(80)几何结构和电子性质进行了研究.几何结构研究表明:在C_(80)H_(80)可能稳定存在的两种同分异构体中,连接12个五边形的20个C原子内部氢化,其余60个C原子外部氢化所形成的结构即H_(20)@C_(80)H_(60)最稳定,其仍然保持I_h对称性.通过对H_(20)@C_(80)H_(60)的能级、前线轨道和态密度分析可知:在H_(20)@C_(80)H_(60)中,H原子的原子轨道与C原子的原子轨道之间在占据态轨道上有较强的杂化,H原子对H_(20)@C_(80)H_(60)的占据态轨道的贡献比较大.其最高占据轨道主要由外部H原子和碳笼来贡献,而最低未占据轨道主要由内部H原子贡献,表明内外H原子在H_(20)@C_(80)H_(60)的化学反应中承担不同的角色.H_(20)@C_(80)H_(60)为闭壳层结构,所有电子都是配对的,表现为非磁性.The generalized gradient approximation based on the density functional theory is used to analyze the geometric and the electronic properties of C80H80. The geometric structure research indicates that between the two possible stable isomers, the isomer with 20 hydrogens connecting 12 pentagons and the 60 others outside is more stable structure. The analyses of the energy level, the orbital wavefunction, and the density of states of H20 @C80H60, show that the atomic orbits of the H and C atoms have strong hybridization on the occupied molecular orbits. The low unoccupied molecular orbital of H20@C80H60 is occupied mainly by the H atoms inside the carbon cage, while the high occupied molecular orbital of H20@C80H60 are occupied partly by the H atoms outside the cage. Therefore, the H atoms inside and outside the cage will play different roles in the chemical reaction involving H20@C80H60. TheH20@C80H60 shows the character of the closed-shell structures with no magnetic moment.

关 键 词：富勒烯 电子结构 密度泛函理论 

分 类 号：O469[理学—凝聚态物理]