Department of Mechanical and Aerospace Engineering, Program in Applied and Computational Mathematics, and Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544, USA.
Phys Rev Lett. 2013 Aug 9;111(6):066402. doi: 10.1103/PhysRevLett.111.066402.
Orbital-free (OF) density functional theory (DFT) directly solves for the electron density rather than the wave function of many electron systems, greatly simplifying and enabling large scale first principles simulations. However, the required approximate noninteracting kinetic energy density functionals and local electron-ion pseudopotentials severely restrict the general applicability of conventional OFDFT. Here, we present a new generation of OFDFT called angular-momentum-dependent (AMD)-OFDFT to harness the accuracy of Kohn-Sham DFT and the simplicity of OFDFT. The angular momenta of electrons are explicitly introduced within atom-centered spheres so that the important ionic core region can be accurately described. In addition to conventional OF total energy functionals, we introduce a crucial nonlocal energy term with a set of AMD energies to correct errors due to the kinetic energy density functional and the local pseudopotential. We find that our AMD-OFDFT formalism offers substantial improvements over conventional OFDFT, as we show for various properties of the transition metal titanium.
无轨道（OF）密度泛函理论（DFT）直接求解多电子系统的电子密度，而不是波函数，极大地简化并实现了大规模的第一性原理模拟。然而，所需的近似非相互作用动能密度泛函和局域电子-离子赝势严重限制了传统 OFDFT 的通用性。在这里，我们提出了一种称为角动量依赖（AMD）-OFDFT 的新一代 OFDFT，以利用 Kohn-Sham DFT 的准确性和 OFDFT 的简单性。电子的角动量在原子中心球体内显式引入，从而可以准确描述重要的离子核区域。除了传统的 OF 总能量泛函，我们引入了一个关键的非局域能量项，其中包含一组 AMD 能量，以纠正由于动能密度泛函和局域赝势引起的误差。我们发现，我们的 AMD-OFDFT 形式主义在各种过渡金属钛的性质上都提供了比传统 OFDFT 实质性的改进。
