灵活电荷模型的影子分子动力学和原子集群扩展
James Goff1, Yu Zhang2, Christian Negre2
1Center for Computing and Research, Sandia National Laboratories, Albuquerque, New Mexico 87185, United States.
Journal of chemical theory and computation
|June 29, 2023
概括
一种新的影子分子动力学方法使用线性原子集群扩张 (ACE) 来高效地建模灵活的电荷潜力. 这种方法可以为氧化和液态水等材料进行稳定和准确的模拟.
科学领域:
- 计算化学计算化学
- 材料科学 材料科学 材料科学
- 理论物理 理论物理
背景情况:
- 精确的分子动力学模拟需要高效和精确的原子间电位.
- 灵活的充电模型对于充电传输系统至关重要,但计算要求很高.
- 现有的方法通常涉及电子结构计算的大量计算开销.
研究的目的:
- 为灵活的电荷模型提供一种新的影子分子动力学方案.
- 整合线性原子集群扩张 (ACE) 进行高效的潜在建模.
- 用氧化和液态水系统来证明该方案的稳定性和准确性.
主要方法:
- 开发了一个基于扩展拉格朗日 (XL) BOMD的影子Born-Oppenheimer分子动力学 (BOMD) 方案.
- 使用线性原子集群膨胀 (ACE) 建模原子间潜力,包括电子负性.
- 模拟自相一致的电荷密度功能紧固结合 (SCC-DFTB) 动态与通过ACE训练的二次电荷平衡 (QEq) 模型.
主要成果:
- 在ACE+XL-QEq分子动力学模拟显示稳定性跨越广泛的温度范围,无论是UO2和水.
- 该方法精确地采样波恩-奥本海默潜在能量表面.
- 对UO2的模拟产生了准确的地面库伦能量,在SCC-DFTB结果的1meV以内.
结论:
- 拟议的影子分子动力学方案与ACE为灵活的电荷模型提供了计算效率高,准确的方法.
- 这种方法为计算上昂贵的机器学习潜力提供了可行的替代方案.
- 该方案成功模拟了各种材料系统的复杂电子结构动态.
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