Grid-based energy density analysis: implementation and assessment.
Grid-based energy density analysis: implementation and assessment.
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DOI：
10.1063/1.2428290
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发表时间：
2007-01
期刊：
影响因子：
--
通讯作者：
Y. Imamura;A. Takahashi;H. Nakai
中科院分区：
文献类型：
--
作者：
Y. Imamura;A. Takahashi;H. Nakai
提出了一种基于网格的能量密度分析方法（grid-EDA），该方法通过空间划分函数将总能量分解为原子能。动能，核吸引力和交换相关功能的网格点上进行评估，并分为原子的贡献。为了减少数值积分的常规方案中的数值误差，电子库仑和HF交换相互作用由伪谱方法评估，该方法首先由Friesner [Chem. Phys. Lett. 116，39（1985）]，并分解成原子贡献。网格EDA使用伪光谱方法成功地确保小于1千卡摩尔的误差，小分子的总能量，并提供可靠的原子能的贡献有问题的锂簇，表现出很强的基础设置依赖于Mulliken型EDA。此外，通过网格EDA估算了Li（48），C（41）H（60）和Mg（32）O（32）等团簇模型的原子化能。Grid-EDA表明，这些模型合理地模拟晶体环境，因为从模型的内部原子估计的原子化能接近实验的结合能。
Grid-based energy density analysis (grid-EDA) that decomposes the total energy into atomic energies by a space-partitioning function is proposed. The kinetic energy, nuclear attraction, and exchange-correlation functional are evaluated on grid points and are split into atomic contributions. To reduce numerical errors in the conventional scheme of numerical integration, the electronic Coulomb and HF exchange interactions are evaluated by the pseudospectral method, which was first applied to an ab initio method by Friesner [Chem. Phys. Lett. 116, 39 (1985)], and are decomposed into atomic contributions. Grid-EDA using the pseudospectral method succeeds in ensuring less than 1 kcalmol error in total energies for small molecules and providing reliable atomic energy contributions for the problematic lithium cluster, which exhibits a strong basis-set dependence for Mulliken-type EDA. Also, site-dependent atomization energies are estimated by grid-EDA for cluster models such as Li(48), C(41)H(60), and Mg(32)O(32). Grid-EDA reveals that these models imitate crystal environments reasonably because atomization energies estimated from the inner atoms of the models are close to the experimental cohesive energies.