固体和液体的计算机模拟,其原子相互作用潜力来自ab initio计算
Ivo Cacelli1, Giorgio Cinacchi, Giacomo Prampolini
1Dipartimento di Chimica e Chimica Industriale, Università di Pisa, via Risorgimento 35, I-56126 Pisa, Italy.
Journal of the American Chemical Society
|October 28, 2004
概括
分子动力学模拟使用量子衍生力场准确地模拟的凝缩相. 该研究通过将模拟结果与热力学和动态性质的实验数据进行比较来验证力场的有效性.
科学领域:
- 物理化学 物理化学
- 计算化学计算化学
- 材料科学 材料科学 材料科学
背景情况:
- 了解在凝结相中的行为对于各种化学和材料应用至关重要.
- 需要精确的分子模型来模拟的热力学和动态性质.
研究的目的:
- 开发和验证使用量子力学计算对的精确分子间潜能.
- 使用开发的力场进行固体和液体的分子动力学模拟.
- 将模拟结果与实验数据和以前的研究进行比较.
主要方法:
- 最初的量子力学计算 (MP2级) 用于生成二元体的相互作用能量数据库.
- 从量子力学数据中得出了一个模型分子间电位.
- 对固体和液体进行了原子分子动力学模拟.
- 计算了热力学,结构和动态性能,并与实验数据进行了比较.
主要成果:
- 开发的力场在复制二元相互作用能量方面表现出令人满意的准确性.
- 模拟显示热力学特性 (例如密度) 和结构特征与实验数据的良好一致.
- 计算的动态特性,包括扩散系数和粘度,与实验测量结果一致.
- 通过与实验结果的全面比较,证实了拟议的力场的可靠性.
结论:
- 量子力学推导的力场对于凝聚相中的的原子模拟可靠.
- 这项研究验证了使用这种模型来预测分子系统的行为.
- 这项工作为进一步调查的特性和相互作用提供了一个强大的计算工具.
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