对于基于Hartree-Fock的对称性适应扰动理论的-D3和-D4分散模型的缓冲函数参数的优化
Austin M Wallace1, C David Sherrill2
1Center for Computational Molecular Science and Technology and School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, USA.
The Journal of chemical physics
|September 18, 2024
概括
适应对称性扰动理论 (SAPT) 的计算可以通过用诸如-D3和-D4这样的校正来取代计算上昂贵的分散项来加快. 与标准SAPT0相比,这些方法对分子间相互作用的准确性有所提高,甚至超过了基于密度函数理论的SAPT.
科学领域:
- 计算化学计算化学
- 量子化学 是一个量子化学.
- 理论化学 理论化学
背景情况:
- 对称适应扰动理论 (SAPT) 通过将它们分解为静电,交换排斥,感应和分散元件来计算分子间相互作用.
- 在SAPT中计算分散项,特别是在SAPT0和SAPT...DFT中,是计算密集的,对大规模计算构成瓶.
- 之前的研究已经探索了使用缓和的非对称模型来近似这些分散项,以减少计算成本.
研究的目的:
- 为了评估SAPT0的准确性,将格里姆的-D3和-D4分散校正用于计算分子间相互作用能量.
- 为了研究这些SAPT0-D模型在不同基础集中的性能,并将它们与标准SAPT0和SAPT (DFT) 方法进行比较.
- 评估三体分散项 (Axilrod-Teller-Muto) 对SAPT0-D模型准确性的影响.
主要方法:
- 进行了对称调整扰动理论 (SAPT0) 的计算,用格里姆的 -D3 和 -D4 校正取代了标准分散项.
- 对 -D3 和 -D4 校正的缓冲参数被优化为使用合集群估计的 jun-cc-pVDZ 基础.
- 使用各种基础集评估了SAPT0-D3和SAPT0-D4的性能,并将其与SAPT0和SAPT (DFT) 结果在一个大型二进制数据集上进行了比较.
主要成果:
- 与标准SAPT0相比,SAPT0-D模型 (使用-D3和-D4校正) 对总相互作用能量的准确性得到了改进,优化的缓冲参数显示了最小的基础设置依赖.
- 发现 -D4 对 -D3 的性能改进是可以忽略不计的,即使对于充电系统而言,理论上预计 -D4 的精度更高.
- 包含三体分散项并没有显著提高测试系统的错误统计,SAPT0-D模型在平均准确性方面表现优于SAPT(DFT) / aug-cc-pVDZ.
结论:
- 将 SAPT0 中昂贵的分散计算替换为 -D3 或 -D4 校正,提供了一个计算效率高的途径,以获得更准确的分子间相互作用能量.
- 对于研究的系统来说, -D4 校正没有比 -D3 提供显著的优势,而三体分散项对于提高这个数据集的准确性并非必不可少.
- SAPT0-D模型为 SAPT ((DFT) 等更苛刻的计算方法提供了令人信服的替代方案,为分子间相互作用研究提供了准确性和效率的有利平衡.
相关概念视频
01:20Types of Damping
6.4K
If the amount of damping in a system is gradually increased, the period and frequency start to become affected because damping opposes, and hence slows, the back and forth motion (the net force is smaller in both directions). If there is a very large amount of damping, the system does not even oscillate; instead, it slowly moves toward equilibrium. In brief, an overdamped system moves slowly towards equilibrium, whereas an underdamped system moves quickly to equilibrium but will oscillate about...
6.4K
01:17Design Example: Underdamped Parallel RLC Circuit
278
Consider designing an oscillator circuit, a crucial component in various electronic devices and systems. The objective is to create an oscillator circuit with specific characteristics: a damped natural frequency of 4 kHz and a damping factor of 4 radians per second. To accomplish this, a parallel RLC circuit is employed, known for its ability to sustain oscillations at a resonant frequency. In this case, the damping factor is pivotal in achieving the desired performance.
Starting with a fixed...
Starting with a fixed...
278
01:19Concept of Resonance and its Characteristics
5.0K
If a driven oscillator needs to resonate at a specific frequency, then very light damping is required. An example of light damping includes playing piano strings and many other musical instruments. Conversely, to achieve small-amplitude oscillations as in a car's suspension system, heavy damping is required. Heavy damping reduces the amplitude, but the tradeoff is that the system responds at more frequencies. Speed bumps and gravel roads prove that even a car's suspension system is not...
5.0K
01:16IR Spectroscopy: Hooke's Law Approximation of Molecular Vibration
1.2K
A covalently bonded heteronuclear diatomic molecule can be modeled as two vibrating masses connected by a spring. The vibrational frequency of the bond can be expressed using an equation derived from Hooke's law, which describes how the force applied to stretch or compress a spring is proportional to the displacement of the spring. In this case, the atoms behave like masses, and the bond acts like a spring.
According to Hooke's law, the vibrational frequency is directly proportional to...
According to Hooke's law, the vibrational frequency is directly proportional to...
1.2K
01:18Second Order systems II
93
In an underdamped second-order system, where the damping ratio ζ is between 0 and 1, a unit-step input results in a transfer function that, when transformed using the inverse Laplace method, reveals the output response. The output exhibits a damped sinusoidal oscillation, and the difference between the input and output is termed the error signal. This error signal also demonstrates damped oscillatory behavior. Eventually, as the system reaches a steady state, the error diminishes to zero.
93
01:24Van der Waals Interactions
63.6K
Atoms and molecules interact with each other through intermolecular forces. These electrostatic forces arise from attractive or repulsive interactions between particles with permanent, partial, or temporary charges. The intermolecular forces between neutral atoms and molecules are ion–dipole, dipole–dipole, and dispersion forces, collectively known as van der Waals forces.
63.6K