利用第一性原理研究La_n(n=2—10)小团簇的结构与稳定性  

First Principles Study of the Structure and Stability of La_n( n= 2—10) Small Clusters

作　　者：王成猛 王海燕[1,2] 高雪云 牛建宇 梁梦斐 WANG Chengmeng;WANG Haiyan;GAO Xueyun;NIU Jianyu;LIANG Mengfei(School of Material and Metallurgy,Inner Mongolia University of Science and Technology,Baotou 014010;Key Laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Resources,Baotou 014010)

机构地区：[1]内蒙古科技大学材料与冶金学院,包头014010 [2]白云鄂博矿多金属资源综合利用重点实验室,包头014010

出　　处：《材料导报》2019年第S02期222-225,共4页Materials Reports

基　　金：国家自然科学基金(51961030);内蒙古自然科学基金(2019MS05013);内蒙古自治区高等学校科技英才支持计划(NJYT-19-A21)~~

摘　　要：团簇作为各种物质由原子分子向大块物质转变过程中出现的特殊物相,代表了凝聚态物质的初始状态。通过对稀土团簇的研究,有助于了解稀土元素在基体材料中的存在形态和作用机理,从而更深入地了解原子团的物理和化学性质,为材料的设计和研究提供理论支持和预见性。本研究利用密度泛函理论中广义梯度近似(GGA)对Lan(n=2—10)团簇进行了结构优化、能量和振动频率分析,得到了La团簇最低能量结构。通过对基态结构的平均结合能、能隙、离解能、二阶能量差以及总态密度的计算和分析,认为原子数n为2、4、6、8时团簇的稳定性较高,费米面处态密度的小幅降低导致了这一奇-偶振荡现象的出现。Clusters represented the initial state of condensed matter,which was a special phase in the transition of various substances from atoms and molecules to bulk substances.Through the study of rare earth clusters,it was helpful to understand the morphology and mechanism of rare earth elements in matrix materials,so as to further understand the physical and chemical properties of atomic clusters,and provide theoretical support and predictability for the design and research of materials.In this paper,the general gradient approximation(GGA)in density functional theory was used to optimize the structure,analyze the energy and vibration frequency of Lan(n=2—10)clusters,and obtained the lowest energy structure of La clusters.By calculating and analyzing the average binding energy,energy gap,dissociation energy,second-order energy diffe-rence and total density of states of the ground state structure,it was considered that the stability of the cluster is higher when the atomic number n was 2,4,6,or 8.A small decrease in the density of states at the Fermi surface led to the occurrence of this odd-even oscillation phenomenon.

关 键 词：密度泛函 LA 团簇 基态结构 稳定性 

分 类 号：TG146.4[一般工业技术—材料科学与工程]