硅铝酸银分子筛吸附氖原子的从头算  

Ab initio calculation for the absorption of neon in molecular sieve of silver silicon-aluminate

作　　者：闫跃阳 王茜[2] 黄整[1] 温述龙 

机构地区：[1]西南交通大学物理科学与技术学院,成都610031 [2]中国工程物理研究院核物理与化学研究所,绵阳621900

出　　处：《原子与分子物理学报》2014年第5期701-705,共5页Journal of Atomic and Molecular Physics

摘　　要：采用基于第一性原理的密度泛函理论(DFT)和局域密度近似(LDA)方法,优化计算硅铝酸银分子筛吸附Ne原子体系的几何结构,能量,电子能带和电荷密度分布.结果表明,硅铝酸银为层状的周期结构,具有直径为a=5.390的孔道.在分子晶体孔道的轴线上,桥O原子附近(I)和表面Ag+离子附近(II)的能量均有利于对Ne原子的吸附.尽管Ne(I)的能量最低,但是SiO4四面体排斥产生的能垒在动力学上不利于Ne原子的吸附.电子能带和电荷分布显示,Ne(II)原子主要受库仑极化的影响,其电子能带的能量较高,Ne(I)原子与桥O原子之间的共价作用能够降低对应的电子能带能量.By using the density functional theory （DFT ） and local density approximation （LDA ） method based on the first principle ,the lattice geometries ,energies ,electronic bands and charge density distri-butions are optimized and calculated for the silicon aluminum acid silver molecular sieve and its deriva-tives of adsorption Neon atoms .The results show that the lattice of silicon aluminum acid silver salt is layered in a periodic structure with holes with holes of a diameter of a =5 .390 ？ .It is beneficial in en-ergy to the adsorption of neon atoms near the bridge oxygen atom （site I ） and the surface Ag ＋ ions （site II） .Although the neon atom at site I has the lowest energy ,but the repulsion barrier from SiO4 tetrahedral is not conducive to the neon absorption in dynamics .The electronic bands and charge distri-butions show s that the neon atom at site II is mainly affected by the Coulomb polarization with higher e-lectronic bands energy ,and the covalent interaction of the neon at site I with the bridge oxygen atom can reduce the electronic band energy .

关 键 词：第一性原理 分子筛吸附 硅铝酸银 氖原子 

分 类 号：O469[理学—凝聚态物理]