Bhattacharjee Abhishek, Jana Subrata, Samal Prasanjit
School of Physical Sciences, National Institute of Science Education and Research, An OCC of Homi Bhabha National Institute, Jatni 752050, India.
Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovoth 76100, Israel.
J Chem Phys. 2024 Jun 14;160(22). doi: 10.1063/5.0204957.
The accuracy of orbital-free density functional theory depends on the approximations made for a Kinetic Energy (KE) functional. Until now, the most accurate KEDFs are based on non-local kernels constructed from the linear response theory of homogeneous electron gas. In this work, we explore beyond the HEG by employing a more general kernel based on the jellium-with-gap model (JGM). The proposed functional incorporates several new features, such as (i) having the correct low momentum(q) limit of the response function for metals and semiconductors without any modeling term, (ii) the underlying kernel is density-independent, and most importantly, (iii) parameter-free. The accuracy and efficiency of the proposed JGM NL-KEDF have been demonstrated for several semiconductors and metals. The encouraging results indicate the utility and predictive power of the JGM kernel for NL KEDF developments. This approach is also physically appealing and practically useful as we have presented a general formalism to incorporate the gap kernel in all existing Lindhard-based functionals.
无轨道密度泛函理论的准确性取决于对动能（KE）泛函所做的近似。到目前为止，最精确的动能密度泛函（KEDF）是基于由均匀电子气的线性响应理论构建的非局部核。在这项工作中，我们通过采用基于有能隙的凝胶模型（JGM）的更通用核来超越均匀电子气模型。所提出的泛函具有几个新特性，例如：（i）对于金属和半导体，无需任何建模项就能得到响应函数正确的低动量（q）极限；（ii）基础核与密度无关，最重要的是，（iii）无参数。所提出的JGM非局部KEDF的准确性和效率已在几种半导体和金属上得到证明。令人鼓舞的结果表明JGM核在非局部KEDF发展中的实用性和预测能力。这种方法在物理上也很有吸引力且实际有用，因为我们提出了一种通用形式，可将能隙核纳入所有现有的基于林哈德的泛函中。
