Nonlocal density functional theory of molecules and solids

天普大学的陶健民获得了化学系化学理论、模型和计算方法项目的一项奖励，以开发和应用理论方法来预测分子和固体的性质。 陶博士的工作重点是被称为“密度泛函理论“（DFT）的理论方法家族。 密度泛函理论在化学界被广泛使用，因为它的速度和能力来表征电子之间的微妙相互作用，决定了分子的能量，形状和行为。 然而，理论的确切形式是未知的;所有现有的形式都是近似的。 陶博士的工作目标是改进DFT，使其能够做出更准确的预测。 Tao团队正在应用他们的新方法研究用于电子设备和太阳能电池的有机材料的特性。他们还在研究他们描述过渡金属基催化剂的新方法的准确性。 他们工作的一个更广泛的影响是一种更通用，更准确和更灵活的DFT形式，可以被世界各地的化学家应用，加速新分子的开发。 此外，陶博士正在为费城地区的本科生和研究生举办DFT暑期研讨会，帮助激励学生从事科学工作，从而扩大参与。 DFT的精度依赖于交换相关能的近似。发展交换相关能作为电子密度的函数是这个理论的主要任务。 现有的泛函对于许多性质是准确的，例如键长、晶格常数和原子化能量，但它们对于带隙、弱相互作用和反应势垒高度往往不太准确。Tao小组正在努力通过对Tao-Mo泛函施加精确的非均匀标度约束，并通过开发局部范围分离或混合泛函来将电子非定域性构建到Tao-Mo泛函中，从而为广泛的属性开发具有高精度的泛函。他们还测试了一个基于局部能隙的动态极化率模型构建的函数。为更广泛的问题开发更精确的DFT方法可能会对化学，物理和材料科学产生广泛的影响。 此外，陶博士还通过暑期研讨会项目促进学生早期参与先进的理论方法。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。

Jianmin Tao of Temple University is supported by an award from the Chemical Theory, Models and Computational Methods Program in the Chemistry Division to develop and apply theoretical methods to predict the properties of molecules and solids. Dr. Tao's work focuses on the family of theoretical methods known as "Density Functional Theory " (DFT). DFT is widely used in the chemistry community because of its speed and ability to characterize the subtle interactions between electrons that determine the energy, shape and behavior of molecules. However, the exact form of the theory is not known; all existing forms are approximations. The goal of Dr. Tao's work is to improve DFT, so that it can make more accurate predictions. The Tao group is applying their new methods to study the properties of organic materials used in electronic devices and solar cells. They are also studying the accuracy of their new methods for the description of transition-metal-based catalysts. One broader impact of their work is a more general, accurate, and flexible form of DFT that can be applied by chemists worldwide, speeding the development of new molecules. In addition, Dr. Tao is developing a summer workshop on DFT for undergraduates and graduate students in the Philadelphia area that helps inspire students to pursue work in the sciences, thus broadening participation. The accuracy of DFT relies on the approximation for the exchange-correlation energy. Development of the exchange-correlation energy as a functional of the electron density is the main task of this theory. Existing functionals are accurate for many properties, such as bond lengths, lattice constants, and atomization energies, but they are often less accurate for band gaps, weak interactions, and reaction barrier heights. The Tao group is working to develop functionals with high accuracy for a broad range of properties by imposing the exact non-uniform scaling constraint on the Tao-Mo functional, and building electronic nonlocality into the Tao-Mo functional by developing local range-separated or hybrid functionals. They are also testing a functional constructed from a model for dynamic polarizability based on the local energy gap. Development of more accurate DFT methods for a wider class of problems may have broad impacts on chemistry, physics, and materials science. In addition, Dr. Tao promote early in engagement by students in advanced theoretical methods through a summer workshop program.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.