标题:Theoretical insight into the structural stability of KZnB _3O _6 polymorphs with different BO _x polyhedral networks
作者:Yang, L.;Fan, W.;Li, Y.;Sun, H.;Wei, L.;Cheng, X.;Zhao, X.
作者机构:[Yang, L] State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China;[ Fan, W] School of Chemistry and Chemical Engineering, 更多
通讯作者:Fan, WL
通讯作者地址:[Fan, WL]Shandong Univ, Sch Chem & Chem Engn, Jinan 250100, Peoples R China.
来源:Inorganic Chemistry: A Research Journal that Includes Bioinorganic, Catalytic, Organometallic, Solid-State, and Synthetic Chemistry and Reaction Dynamics
出版年:2012
卷:51
期:12
页码:6762-6770
DOI:10.1021/ic300469s
摘要:In general, the presence of shared edges of polyhedra for high-valence low-coordinated small cations is rarely seen except under extreme conditions such as high pressure. However, the ambient-pressure synthesis of KZnB _3O _6 built of edge-sharing BO _4 tetrahedra is contrary to this. By investigating the molecular dynamics, lattice dynamics, and electronic properties via density functional theory, we studied the origin of the phase stability of the edge-sharing (es) and \"corner-sharing (cs)\" KZnB _3O _6. Lattice dynamics results show that there are no phonon anomalies that could lead to the instability of es-KZnB _3O _6, which is consistent with molecular dynamics analysis. For \"cs-KZnB _3O _6\", a soft mode at the G point in the phonon dispersion is identified that reflects the dynamic instability with respect to small distortions. Eigenvector analysis of the soft mode of \"cs-KZnB _3O _6\" indicates that the instability comes from the linkage of ZnO _5 polyhedra rather than BO _x polyhedra. Electronic property calculation indicates that the edge-sharing BO _4 polyhedra connected by the longest B-O σ bonds provide a solid framework for es-KZnB _3O _6. In the case of \"cs-KZnB _3O _6\", the overlong Zn-O bond possesses the smallest covalent nature and the least orbital overlap among the bonds in a ZnO _5 polyhedron, and these two features of the electronic structure reduce the stability of \"cs-KZnB _3O _6\" compared to es-KZnB _3O _6. The electronic property calculation further confirms the results obtained from lattice dynamics analysis.
收录类别:SCOPUS;SCIE
WOS核心被引频次:3
Scopus被引频次:6
资源类型:期刊论文
原文链接:https://www.scopus.com/inward/record.uri?eid=2-s2.0-84862579562&doi=10.1021%2fic300469s&partnerID=40&md5=fa29ea41b090ceaf02fb813614a6852e
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