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Frustrated and Allowed Structural Transitions: Towards a Predictive Framework for the Structural Chemistry of Intermetallic Phases

受挫和允许的结构转变：金属间相结构化学的预测框架

基本信息

批准号：
1809594
负责人：
Daniel Fredrickson
金额：
$ 46.61万
依托单位：
University of Wisconsin-Madison
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-08-01 至 2022-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1809594&HistoricalAwards=false
关键词：
Frustrated Allowed Structural Transitions Towards

项目摘要

NON-TECHNICAL SUMMARY: The development of new technologies is closely connected to the discovery and optimization of new solid state materials. Intermetallic phases-compounds formed upon alloying metals together-represent a rich source of such materials, as the periodic table offers virtually infinite possible combinations and ratios of metallic elements. However, the realization of useful applications based on intermetallic phases is limited by the inability to control their often complex and unpredictable geometrical arrangements at the atomic level. This project, supported by the Solid State and Materials Chemistry program in the Division of Materials Research at NSF, is promoting the progress of science through the creation of chemical principles for understanding the crystal structures of these materials and eventually guiding them in ways that enhance a desired property. Theory is used to identify ways that the different aspects of atoms (such as their sizes and ways of bonding) can cooperate to stabilize structures and facilitate transformations between structures. These conclusions then guide the experimental discovery of new compounds, with their structures and behavior providing feedback for theory. In addition, this project continues the development of online resources that make solid state and materials chemistry accessible for the public, including the living textbook "Interactive Solid State Chemistry" (available as part of the Chemical Education Digital Library), and "Science through Comics". The project also provides educational experiences for undergraduate researchers as well as an internship for a high-school student from a demographic group underrepresented in the sciences each summer. TECHNICAL SUMMARY: The structures of intermetallic phases - solid state compounds derived from metallic and metalloid elements - are known to be governed by the same chemical properties as molecules: electron counts, atomic size requirements, and electronegativities. However, in contrast to molecular chemistry, no broadly applicable predictive schemes for guiding intermetallic structural chemistry through solid state synthesis has been realized yet, which is a limiting factor in utilizing the full potential of these compounds as applied materials. This project, funded by the Solid State and Materials Chemistry Program in the Division of Materials Research at NSF, draws on recently developed theoretical tools for visualizing strains in atomic packing and local electron configurations in intermetallics to build a conceptual framework for predicting structural phenomena in these compounds: the Frustrated and Allowed Structural Transitions (FAST) model. Here, potential rearrangements of a parent structure are divided into those that are frustrated or allowed, depending on whether the primary factor driving the transition (either atomic packing or electronics) is supported or impeded by the respective second factor, with allowed transformations predicted to be readily realizable experimentally. Using a combination of theory and experiment, the principle investigator's research group tests and refines this model through the anticipation and discovery of new structural progressions (including diffusionless phase transitions) and the selective stabilization of shallow metastable structures in binary systems through elemental substitution. Therefore they examine a vast range of intermetallic structures through the FAST approach in search of hallmarks of responsiveness in the electronic and packing factors (the violation of electron counting rules and intense chemical pressure features, respectively). Those phases for which previously unobserved structural chemistry is deemed allowed by this model are prioritized for experimental investigation.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

非技术总结：新技术的发展与新固态材料的发现和优化密切相关。金属间化合物相--金属合金化后形成的化合物--代表了这种材料的丰富来源，因为元素周期表提供了几乎无限可能的金属元素组合和比例。然而，基于金属间相的有用应用的实现受限于不能在原子水平上控制它们通常复杂且不可预测的几何布置。该项目由NSF材料研究部的固态和材料化学计划支持，通过创建用于理解这些材料的晶体结构的化学原理并最终以增强所需性能的方式指导它们来促进科学的进步。理论用于确定原子的不同方面（例如它们的大小和键合方式）可以合作以稳定结构并促进结构之间的转换。然后，这些结论指导新化合物的实验发现，它们的结构和行为为理论提供反馈。此外，该项目继续开发在线资源，使公众可以访问固态和材料化学，包括生活教科书“互动固态化学”（作为化学教育数字图书馆的一部分）和“科学通过漫画”。该项目还为本科研究人员提供教育经验，并为每年夏天在科学领域代表性不足的高中生提供实习机会。技术概要：金属间相的结构--由金属和类金属元素衍生的固态化合物--已知受与分子相同的化学性质支配：电子计数、原子尺寸要求和电负性。然而，与分子化学相反，尚未实现用于通过固态合成来指导金属间结构化学的广泛适用的预测方案，这是利用这些化合物作为应用材料的全部潜力的限制因素。该项目由NSF材料研究部的固态和材料化学计划资助，利用最近开发的理论工具，用于可视化金属间化合物中原子堆积和局部电子构型中的应变，以建立预测这些化合物中结构现象的概念框架：受挫折和允许的结构转变（FAST）模型。在这里，母结构的潜在重排被分为那些被挫败或允许的重排，这取决于驱动转变的主要因素（原子堆积或电子学）是否受到相应的第二因素的支持或阻碍，允许的转换预测是容易实现的实验。使用理论和实验相结合，主要研究者的研究小组通过预测和发现新的结构进展（包括无扩散相变）和通过元素替代选择性稳定二元系统中的浅亚稳结构来测试和改进这个模型。因此，他们通过FAST方法检查了大量的金属间化合物结构，以寻找电子和填充因子中的响应性标志（分别违反电子计数规则和强烈的化学压力特征）。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

期刊论文数量（9）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

High electrical conductivity in the epitaxial polar metals LaAuGe and LaPtSb

DOI：
10.1063/1.5132339
发表时间：
2019-12-01
期刊：
APL MATERIALS
影响因子：
6.1
作者：
Du, Dongxue;Lim, Amber;Kawasaki, Jason K.
通讯作者：
Kawasaki, Jason K.

Discerning Chemical Pressure amidst Weak Potentials: Vibrational Modes and Dumbbell/Atom Substitution in Intermetallic Aluminides

DOI：
10.1021/acs.jpca.8b07419
发表时间：
2018-10-25
期刊：
JOURNAL OF PHYSICAL CHEMISTRY A
影响因子：
2.9
作者：
Hilleke, Katerina P.;Fredrickson, Daniel C.
通讯作者：
Fredrickson, Daniel C.

Pseudogap Control of Physical and Chemical Properties in CeFeSi-Type Intermetallics

CeFeSi型金属间化合物物理和化学性质的赝间隙控制

DOI：
10.1021/acs.inorgchem.8b03539
发表时间：
2019
期刊：
Inorganic Chemistry
影响因子：
4.6
作者：
Wu, Jiazhen;Lu, Erdong;Li, Jiang;Lu, Yangfan;Kitano, Masaaki;Fredrickson, Daniel C.;Inoshita, Takeshi;Hosono, Hideo
通讯作者：
Hosono, Hideo

Templating Structural Progessions in Intermetallics: How Chemical Pressure Directs Helix Formation in the Nowotny Chimney Ladders

金属间化合物的模板化结构进展：化学压力如何引导诺沃特尼烟囱梯中的螺旋形成