Development of Novel Exchange-Correlation Functionals & Applications

莱斯大学的古斯塔沃·斯库里亚获得了理论和计算化学项目颁发的奖项，该奖项旨在开发密度泛函理论(DFT)中更准确和更有效的近似。这项工作有望显著提高密度泛函理论对分子和固体的基态和激发态的适用性。正在进行的项目涉及本地混合动力车和本地射程分离等概念。Scueria集团正在开发的新功能正被应用于碳纳米管和石墨烯纳米带，这两种材料都是很有前途的纳米技术应用材料。计算量子化学为预测化学性质和解释新的化学现象提供了必要的工具。Kohn-Sham密度泛函理论(DFT)是量子化学中应用最广泛的方法。DFT最大的吸引力在于，它以比相关波函数法等其他技术低得多的计算成本提供有用的准确预测。线性定标技术的应用可以使DFT即使对于非常大的系统(分子和固体)也是负担得起的。这使得密度泛函理论成为对这些系统中的电导等量子效应进行第一性原理预测的唯一方法。虽然DFT在形式上是精确的，但实际上它需要近似总能量的一个很大组成部分：交换-关联相互作用。离散傅里叶变换的准确性和最终的有用性受到精确交换相关泛函近似质量的限制。现有的近似泛函是相当精确的，但在许多性质上失去了相对于现代波函数方法的优势。在过去的几年里，PI的研究小组一直在积极开发新的交换相关泛函。他的团队开发的许多官能团(例如，VSXC、TPSS、HSE)被广泛应用于学术界、国家实验室和工业。目前的工作预计将产生同样广泛的影响，并对各级学生的培训作出贡献。

Gustavo Scuseria of Rice University is supported by an award from the Theoretical and Computational Chemistry program for research to develop more accurate and efficient approximations in density functional theory (DFT). The work is expected to significantly enhance DFT's applicability to ground and excited electronic states of both molecules and solids. The projects being pursued involve concepts such as local hybrids and local range separation. The new functionals being developed in the Scuseria group are being applied to carbon nanotubes and graphene nanoribbons, both of which are promising materials for nanotechnology applications.Computational quantum chemistry has provided essential tools for predicting chemical properties and interpreting new chemical phenomena. Kohn-Sham density functional theory (DFT) is the most widely used method in quantum chemistry. The strongest appeal of DFT is that it delivers usefully accurate predictions at a computational cost much lower than other techniques such as correlated wavefunction methods. Application of linear scaling techniques can make DFT affordable even for very large systems (both molecules and solids). This makes DFT the only method available for first-principles prediction of quantum effects such as conductance in these systems. While DFT is formally exact, in practice it requires approximating a large component of the total energy: the exchange-correlation interaction. DFT's accuracy, and ultimate usefulness, is limited by the quality of approximations to the exact exchange-correlation functional. Existing approximate functionals are reasonably accurate, but lose their edge over modern wavefunction methods for many properties. The PI's research group has been active in the development of novel exchange-correlation functionals for the last several years. Many of the functionals developed in his group (e.g., VSXC,TPSS, HSE) are widely used in academia, national laboratories, and industry. The current work is expected to have an equally broad impact and to contribute to the training of students at all levels.