Tuning Reactivity, Electronic Structure and Properties via Pressure: Predicting Novel Superconductors

通过压力调节反应性、电子结构和特性：预测新型超导体

• 批准号: 1505817
• 负责人: Eva Zurek
• 金额: $ 34.5万
• 依托单位: SUNY at Buffalo
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-06-15 至 2019-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1505817&HistoricalAwards=false
• 关键词: Tuning; Reactivity; Electronic; Structure; Properties

NON-TECHNICAL SUMMARYThis award supports research and education whose ultimate goal is to rationally design new superconductors, materials through which electric current can flow without losing energy, via computational modeling. Replacing copper wires with superconducting power lines would have a tremendous impact on the electrical power infrastructure of the USA, but unfortunately all of the currently known superconductors must be cooled down to very low temperatures before they become superconducting. Research suggests that hydrogen-rich solids could potentially behave as superconductors at high temperatures, and they will therefore be the focus of this project.Just like diamond can be synthesized at high pressure within the earth, researchers can use pressure as a variable to create new materials with unusual properties that may remain stable when the pressure is released. A number of new superconductors have been synthesized in this way. However, since these experiments are very difficult to perform, computational predictions can accelerate new materials discovery. The PI will carry out calculations based upon quantum mechanics to predict promising new targets for synthesis, and collaborate with leading experimental groups in high-pressure research that will attempt to synthesize these materials. To advance this goal the PI will further develop a set of software tools, which can be used to computationally predict the structure of a solid without any experimental information. These tools are made freely available to the materials science, physics and chemistry communities, thereby advancing rational materials design as well as current and future discoveries in science and engineering. Graduate and undergraduate students will be trained in rational computational materials design and programming, thereby preparing them for future careers where synergy between theory, computation and experiment leads to innovation. Student and faculty exchange with a primarily undergraduate, minority serving institution (California State University San Bernardino) will expose these students to research and future career opportunities in STEM fields, and train them in state-of-the-art materials modeling techniques. TECHNICAL SUMMARYThis award supports theoretical research and education that will lead towards the rational design of novel superconductors. The PI will computationally predict the crystal structures of materials with unique stoichiometries and structures that can be synthesized using the pressure variable, and study their electronic structures and properties via first-principles calculations. Focus will be placed on compounds containing hydrogen doped with a p-block element because strong covalent bonds between the p-block atoms may render these structures metastable upon decompression to atmospheric pressures, and both experiment and theory suggest that binary hydrides may have a high superconducting transition temperature. The PI will also study binary polar intermetallics, as it has already been demonstrated that many of these can be synthesized at modest pressures, remain stable at atmospheric conditions, and behave as BCS superconductors. New, perhaps completely unexpected, chemistry and totally new types of materials will be discovered theoretically, and the predictions will be confirmed by leading experimental groups in high pressure research. The award will also support the further development of the "XtalOpt" evolutionary algorithm, which can be used to predict the structure of an extended system given only its stoichiometry. Key developments will increase the size and complexity of the unit cells that can be predicted without any experimental information, and accelerate the progress of a priori structure prediction for extended systems. The crystallography suite within the highly popular chemical builder, editor and visualizer "Avogadro", will be further advanced. Because XtalOpt and Avogadro are written under licenses approved by the Open Source Initiative, the program code can be re-used, thereby contributing towards cyberinfrastructure as well as current and future discoveries in science and engineering. Graduate and undergraduate students will be trained in rational computational materials design and programming, thereby preparing them for future careers where synergy between theory, computation and experiment leads to innovation. Student and faculty exchange with a primarily undergraduate, minority serving institution (California State University San Bernardino) will expose these students to research and future career opportunities in STEM fields, and train them in state-of-the-art materials modeling techniques.

非技术摘要这一奖项支持研究和教育，其最终目标是合理地设计新的超导体，电流可以通过计算建模而不会损失能量的材料。用超导电源线代替铜线将对美国的电力基础设施产生巨大影响，但不幸的是，在它们成为超导之前，所有当前已知的超导体都必须冷却至非常低的温度。研究表明，富含氢的固体可能会在高温下作为超导体行为，因此它们将成为该项目的焦点。就像钻石一样，可以在地球内的高压下合成钻石，研究人员可以将压力用作创建具有不寻常特性的新材料，在释放压力时可能保持稳定。许多新的超导体已通过这种方式合成。但是，由于这些实验很难执行，因此计算预测可以加速​​新材料的发现。 PI将基于量子力学进行计算，以预测有希望的新目标合成目标，并与领先的实验组合作在高压研究中将尝试合成这些材料。为了促进这一目标，PI将进一步开发一组软件工具，可用于计算无需任何实验信息的固体结构。这些工具可自由提供给材料科学，物理和化学社区，从而推进了理性材料设计以及科学和工程学的当前和未来发现。研究生和本科生将接受理性计算材料设计和编程的培训，从而为未来的职业做准备，在这些职业中，理论，计算和实验之间的协同作用会导致创新。与主要是本科，少数民族服务机构（加利福尼亚州立大学圣贝纳迪诺）的学生和教师交流将使这些学生在STEM领域的研究和未来的职业机会，并以最先进的材料建模技术进行培训。技术摘要这一奖项支持理论研究和教育，这将导致新型超导体的合理设计。 PI将在计算上预测具有独特化学计量和结构的材料的晶体结构，可以使用压力变量合成，并通过第一原理计算研究其电子结构和性能。将重点放在含有P块元件掺杂的氢气的化合物上，因为P块原子之间的强共价键可能在解压缩到大气压时会使这些结构使这些结构构成，并且实验和理论都表明，二进制氢化物可能具有较高的超导过渡温度。 PI还将研究二进制极性金属中的金属间学，因为已经证明其中许多可以在适度的压力下合成，在大气条件下保持稳定，并且像BCS超导体一样行为。理论上将发现新的，也许是完全出乎意料的化学和全新的材料类型，并且在高压研究中领先的实验组将证实这些预测。 该奖项还将支持“ Xtalopt”进化算法的进一步发展，该算法可用于预测仅在化学计量的情况下进行扩展系统的结构。关键的发展将增加无需任何实验信息即可预测的单位单元的大小和复杂性，并加速扩展系统的先验结构预测的进度。众所周知的化学构建器，编辑和可视化器“ Avogadro”中的晶体学套件将进一步提出。由于Xtalopt和Avogadro是经开源倡议批准的许可书撰写的，因此可以重新使用程序代码，从而为网络基础设施以及科学和工程学的当前和未来发现做出贡献。研究生和本科生将接受理性计算材料设计和编程的培训，从而为未来的职业做准备，在这些职业中，理论，计算和实验之间的协同作用会导致创新。与主要是本科，少数民族服务机构（加利福尼亚州立大学圣贝纳迪诺）的学生和教师交流将使这些学生在STEM领域的研究和未来的职业机会，并以最先进的材料建模技术进行培训。