Development of Novel Exchange-Correlation Functionals & Applications

莱斯大学的Gustavo Scuseria获得了理论和计算化学计划的奖项，用于研究在密度泛函理论（DFT）中开发更准确和有效的近似。 这项工作预计将显着提高DFT的适用性，基态和激发电子状态的分子和固体。正在实施的项目涉及地方杂交和地方分布区分离等概念。Scuseria小组正在开发的新泛函正被应用于碳纳米管和石墨烯纳米带，这两种材料都是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最大的吸引力是它以比其他技术（如相关波函数方法）低得多的计算成本提供有用的准确预测。线性标度技术的应用可以使DFT甚至对于非常大的系统（分子和固体）也可以负担得起。 这使得DFT的唯一方法可用于第一原理预测量子效应，如电导在这些系统。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大部分：交换相关相互作用。DFT的准确性和最终的实用性受到精确交换相关泛函的近似质量的限制。现有的近似泛函是相当准确的，但失去了现代波函数方法的许多属性的优势。在过去的几年里，PI的研究小组一直活跃在新型交换相关泛函的开发中。他的小组中开发的许多泛函（例如，VSXC、TPSS、HSE）广泛应用于学术界、国家实验室和工业界。预计目前的工作将产生同样广泛的影响，并有助于培训各级学生。

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.