Ordering phenomena in ternary transition-metal dichalcogenides:Critical role of lattice symmetry and vdW interaction  

作　　者：Tianxu Zhang Linggang Zhu Hanyu Liu Jian Zhou Zhimei Sun 

机构地区：[1]School of Materials Science and Engineering,Beihang University,Beijing,China [2]Center for Integrated Computational Materials Engineering,International Research Institute for Multidisciplinary Science,Beihang University,Beijing,China

出　　处：《Materials Genome Engineering Advances》2023年第2期77-88,共12页材料基因工程前沿（英文）

基　　金：supported by the National Key Research and Development Program of China(Grant No.2022YFB3807200);the National Natural Science Foundation of China(No.52173216);the Fundamental Research Funds for the Central Universities.

摘　　要：Concentrated solid solution materials with huge compositional design space and normally unexpected property attract extensive interests of researchers.In these emerging materials,local composition fluctuation such as short-range order(SRO),has been observed and found to have nontrivial effects on material properties,and thus can be utilized as an additional degree of freedom for material optimization.To exploit SRO,its interplay with factors beyond element-level property,including lattice symmetry and bonding environment,should be clarified.In this work by using layered transition-metal dichalcogenide Mo(X0.5X00.5)2(X/X0=O,S,Se,or Te)with mixed element in the non-metal sublattice as the platform,the ordering phenomena are systematically studied using multiscale simulations.As expected,electronegativity difference between X and X0 strongly regulates SRO.Additionally,SRO and long-range order(LRO)are observed in the 2H and T/T0 phase of MoXX0,respectively,indicating a strong influence of lattice symmetry on SRO.More importantly,as vdW interaction is introduced,the SRO structure in 2HMoXX0 bilayer can be re-configured,while the LRO in T/T0-MoXX0 remains unchanged.Electronic insights for SRO and the resultant property variation are obtained.This work presents a thorough understanding of SRO in bonding complex systems,benefiting the SRO-guided material designs.

关 键 词：ELECTRONEGATIVITY first-principles calculation Monte Carlo simulation short/long-range order transition-metal dichalcogenide vdW interaction 

分 类 号：TB381[一般工业技术—材料科学与工程]