氧离子导体β-La_2Mo_2O_9结构性质的第一性原理研究
Research on crystal structure of β-La2Mo_2O_9 using first-principle theory

侯春菊 ¹ 张旭 ² 董太源 ¹ 孔详山 ³

文摘	采用第一性原理方法研究了β-La_2Mo_2O_9结构性质.研究发现结构中Mo和周围的O形成MoO_4或MoO_5两种形式的多面体,La则形成LaO_8和LaO_7多面体.O(1)、O(2)、O(3)三种氧位置的占有率分别为100%、91.7%和25%,与实验相符.对Mo-O(1)键长分析表明,在MoO_4和MoO_5两种多面体中Mo-O(1)键长劈裂成两种键长形式.所有结构组态可通过P2_13空间群的相应操作而互相转换,显示结构具有P2_13空间群的对称性.模拟结果可能是β-La_2Mo_2O_9结构在空间的局域或者本征极小结构.
其他语种文摘	. The structure of β-La_2Mo_2O_9 was studied by using two methods based on first-principles theory. Each Mo cation is surrounded by four or five O-ions, forming MoO_4 tetrahedra or MoO_5 hexahedra,La has LaO_8 and LaO_7 polyhedra. It is found that the occupancies of three crystallographic distinct O sites O(1), O(2) and O(3) are 100%, 91.7% and 25%, respectively, consistent with experiments. The analysis of Mo-O(1) bond length demonstrates the split of O(1) sites into two groups. All configurations are related to each other by one of 12 symmetry operations of P2_1 3 space group, suggesting that the structure observed experimentally may be interpreted as a time and spatial average of these local or inherent structures.
来源	四川大学学报. 自然科学版 ,2010,47(1):102-108 【核心库】
关键词	氧离子导体 ; β-La_2Mo_2O_9 ; 第一性原理 ; 氧空位
地址	1. 江西理工大学理学院, 江西, 赣州, 341000 2. 江西理工大学材料与化工程学院, 江西, 赣州, 341000 3. 中国科学院固体物理研究所, 安徽, 合肥, 230031
语种	中文
文献类型	研究性论文
ISSN	0490-6756
学科	物理学
基金	国家自然科学基金
文献收藏号	CSCD:3821090