Department of Chemistry, Texas Christian University, Fort Worth, Texas 76109, USA.
J Chem Phys. 2009 Dec 21;131(23):234111. doi: 10.1063/1.3274824.
This work presents a new nonlocal model for the exchange energy density. The model is obtained from the product of the Kohn-Sham one-particle density matrix used to construct exact [Hartree-Fock-like (HF)] exchange, and an approximate density matrix used to construct local spin-density approximation (LSDA) exchange. The proposed exchange energy density has useful formal properties, including correct spin and coordinate scaling and the correct uniform limit. It can readily be evaluated in finite basis sets, with a computational scaling intermediate between HF exchange and semilocal quantities such as the noninteracting kinetic energy density. Applications to representative systems indicate that its properties are typically intermediate between HF and LSDA exchange, and often similar to global hybrids of HF and LSDA exchange. The model is proposed as a novel "Rung 3.5" ingredient for constructing approximate exchange-correlation functionals.
这项工作提出了一种新的交换能密度的非局域模型。该模型是由用于构建精确 [哈特ree-fock 类 (hf)] 交换的 kohn-sham 单粒子密度矩阵与用于构建局域自旋密度近似 (lsda) 交换的近似密度矩阵的乘积得到的。所提出的交换能密度具有有用的形式性质，包括正确的自旋和坐标缩放以及正确的均匀极限。它可以很容易地在有限的基集上进行评估，其计算标度介于 hf 交换和非相互作用动能密度等半局域量之间。对代表性体系的应用表明，其性质通常介于 hf 和 lsda 交换之间，并且通常类似于 hf 和 lsda 交换的全局混合。该模型被提议作为构建近似交换相关泛函的新的“第 3.5 步”成分。
