关于"密度函数理论正在偏离正确函数的路径"的评论
Michael G Medvedev1,2, Ivan S Bushmarinov3, Jianwei Sun4
1X-ray Structural Laboratory, A. N. Nesmeyanov Institute of Organoelement Compounds RAS, 119991 Moscow, Russian Federation. medvedev.m.g@gmail.com perdew@temple.edu.
Science (New York, N.Y.)
|May 6, 2017
概括
密度配合中的灵活功能形式增强了插值,但降低了分子结合的预测能力. 尽管对原子密度的相关性存在担忧,但这一发现仍然存在.
科学领域:
- 计算化学
- 材料科学
背景情况:
- 密度函数理论 (DFT) 对于预测材料性能至关重要.
- 开发准确和预测密度函数是一个持续的挑战.
- 选择合适的功能形式会影响 DFT 的准确性.
研究的目的:
- 评估灵活的功能形式对密度适配的影响.
- 评估密度函数的概括性和预测能力.
- 解决关于原子密度在装配过程中的相关性的批评.
主要方法:
- 使用无约束的灵活功能形式进行密度适配.
- 分析得到的密度函数的插入与预测能力.
- 将结果与已知方法进行比较,并解决特定的批评问题.
主要成果:
- 不受制约的灵活功能形式增加了插入能力.
- 这种方法显著降低了密度函数的广泛预测能力.
- 这项研究证实,适配的灵活性可能会导致过度适配.
结论:
- 虽然灵活的拟合增强了插入,但它损害了密度函数的广泛预测准确性.
- 关于插入和预测之间的权衡的主要结论仍然有效.
- 需要进一步的研究来平衡配合灵活性与预测概括性.
更多相关视频
相关概念视频
03:51Molecular Orbital Theory II
28.0K
Molecular Orbital Energy Diagrams
28.0K
02:35Molecular Orbital Theory I
48.2K
Overview of Molecular Orbital Theory
48.2K
02:38Valence Bond Theory and Hybridized Orbitals
31.8K
According to valence bond theory, a covalent bond results when: (1) an orbital on one atom overlaps an orbital on a second atom, and (2) the single electrons in each orbital combine to form an electron pair. The strength of a covalent bond depends on the extent of overlap of the orbitals involved. Maximum overlap is possible when the orbitals overlap on a direct line between the two nuclei.
A σ bond (single bond in a Lewis structure) is a covalent bond in which the electron density is...
A σ bond (single bond in a Lewis structure) is a covalent bond in which the electron density is...
31.8K
01:10Van der Waals Equation
6.7K
The ideal gas law is an approximation that works well at high temperatures and low pressures. The van der Waals equation of state (named after the Dutch physicist Johannes van der Waals, 1837−1923) improves it by considering two factors.
First, the attractive forces between molecules, which are stronger at higher densities and reduce the pressure, are considered by adding to the pressure a term equal to the square of the molar density multiplied by a positive coefficient a. Second, the volume...
First, the attractive forces between molecules, which are stronger at higher densities and reduce the pressure, are considered by adding to the pressure a term equal to the square of the molar density multiplied by a positive coefficient a. Second, the volume...
6.7K
01:28Debye–Huckel–Onsager Conductance Equation
13
The Debye-Hückel-Onsager equation is a cornerstone of physical chemistry, providing a method to determine the molar conductance (Λm) and molar conductance at infinite dilution (Λ°m) for uni-univalent electrolytes.Uni-univalent electrolytes are electrolytes that dissociate in solution to produce one cation with a +1 charge and one anion with a –1 charge per formula unit.This equation addresses two crucial phenomena: the asymmetry effect and the electrophoretic effect.
13
01:26The Van der Waals Equation
19
The ideal gas law is based on two simplifying assumptions: first, that there are no intermolecular attractions between gas molecules, and second, that the volume occupied by the molecules themselves is negligible compared with the volume of the container. However, these assumptions don't hold up under all conditions - specifically, at high pressures and low temperatures, as gas tends to deviate from ideal gas behavior.The van der Waals equation is an enhanced version of the ideal gas law,...
19