The Generalized Cluster Expansion: A Tool for Representing Structure-Property Relationships

广义簇展开：表示结构-性质关系的工具

• 批准号: 0907669
• 负责人: Axel van de Walle
• 金额: $ 30.6万
• 依托单位: California Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-15 至 2013-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0907669&HistoricalAwards=false
• 关键词: Generalized; Cluster; Expansion; Tool; Representing

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).TECHNICAL SUMMARYStructure-property relationships have long guided materials discovery and improved our understanding of the mechanisms underlying diverse physical phenomena. This award supports developing a set of theoretical and computational tools to determine and efficiently represent the relationship between the atomic structure of a compound and a given material property. The starting point is the cluster expansion formalism, which can express the relationship between a scalar material property and a crystalline alloy?s atomic configuration. This project generalizes this formalism to tensor-valued and nonuniform/nonisotropic material properties.The resulting generalized cluster expansion coupled with first-principles calculations will be applied in three general areas:(1) Phase field modeling: the generalized cluster expansion can encode the relationship between various phase fields representing the state of order of an alloy and tensorial properties, such as elastic constants or lattice parameters that enter the mesoscopic equation of motion of the simulated system.(2) Automated discovery of atomistic mechanisms: An illustrative application is the determination of the atomic-level origins of specific features in the phonon spectrum through the use of environment-dependent force constants tensors. Here, each term in the generalized cluster expansion would provide independent geometrical insight regarding the mechanisms at work.(3) Materials discovery and/or optimization: The generalized cluster expansion will be used to demonstrate an efficient computational combinatorial screening of a large number of candidate superlattices in search of one with the desired combination of properties relevant for device design.Software tools developed in this project will be included within the Alloy Theoretic Automated Toolkit, a widely used software package that the PI has made available on the world-wide web. This project will promote integration of research and education as well as diversity in science by contributing to the Materials Partnership Program established by Caltech?s Center for the Science and Engineering of Materials which recruits undergraduates from California State University, Los Angeles in collaborative research projects with Caltech.NON-TECHNICAL SUMMARYThis award supports theoretical and computational research that will develop new computational algorithms and tools for determining the relationship between the structure of a specific, possibly candidate, material and its properties. The PI will extend an existing approach to enable inclusion of a larger set of materials properties that enhance the power and utility of the method. The research effort contributes to the effort to discover new materials with desired properties using computation and starting only with the identity of the constituent atoms. This research may lead to the discovery of new materials with desired properties for technological applications, or optimizing the properties of existing materials or materials structures. New materials for optoelectronic devices are a specific focus of this project. Software tools developed in this project will be made available to the broader materials research community and will contribute to its cyberinfrastructure.

该奖项是根据2009年的《美国复苏与再投资法》（公法111-5）资助的。技术摘要结构 - 统治关系长期以来一直指导材料发现，并提高了我们对多种物理现象的机制的理解。该奖项支持开发一组理论和计算工具，以确定和有效地表示化合物的原子结构与给定材料属性之间的关系。起点是群集扩展形式主义，它可以表达标量材料属性与结晶合金的原子构型之间的关系。 This project generalizes this formalism to tensor-valued and nonuniform/nonisotropic material properties.The resulting generalized cluster expansion coupled with first-principles calculations will be applied in three general areas:(1) Phase field modeling: the generalized cluster expansion can encode the relationship between various phase fields representing the state of order of an alloy and tensorial properties, such as elastic constants or lattice parameters that enter the （2）原子机制的自动发现：说明性应用是通过使用依赖环境依赖性力常数张贴器来确定原子级特定特征的原子水平来源。在这里，广义集群扩展中的每个术语都将提供有关工作机制的独立几何见解。（3）材料发现和/或优化：广义群集扩展将用于证明有效的计算组合筛选，以搜索一系列属性的构图，以将其组合在设备设计中。 Toolkit是PI在全球网络上提供的广泛使用的软件包。该项目将通过为Caltech的科学与工程中心建立的材料合作计划贡献材料和工程中心建立的材料合作计划，从而促进研究和教育的融合，并促进科学的多样性，这些材料中心招募了加利福尼亚州立大学，洛杉矶大学，与Caltech.non-non-technical-themental Intures的工具之间的工具，该工具与新的计算机之间的工具相加特定的，可能是候选的材料及其特性。 PI将扩展现有方法，以促进一组较大的材料属性，以增强该方法的功能和效用。研究工作有助于努力使用计算发现具有所需属性的新材料，并且仅从成分原子的身份开始。这项研究可能会导致发现具有技术应用所需特性的新材料，或优化现有材料或材料结构的特性。光电设备的新材料是该项目的特定重点。 该项目中开发的软件工具将提供给更广泛的材料研究界，并将为其网络基础架构做出贡献。