对Si-O-C-H分子热化学密度函数的评估
Ingeborg-Helene Svenum1, Francesca Lønstad Bleken2, Stefan Andersson1
1SINTEF Industry, P.O. Box 4760, Torgarden, Trondheim 7465, Norway.
The journal of physical chemistry. A
|October 22, 2025
概括
对Si-O-C-H分子的精确计算化学方法是使用单和双激发的合集群以及三次激发 (CCSD(T)) 和密度函数理论 (DFT) 的扰动性处理. DFT功能M06-2X在形成计算的度方面取得了卓越的成绩.
科学领域:
- 计算化学是一种计算化学.
- 量子化学是一种量子化学.
- 材料科学是一种材料科学.
背景情况:
- -氧-碳- (Si-O-C-H) 分子系统在各种化学应用中至关重要.
- 这些系统的准确计算数据对于预测它们的特性和反应性至关重要.
- 现有的计算方法需要与高级理论基准进行严格的验证.
研究的目的:
- 使用高级理论方法计算Si-O-C-H分子的能量和振动频率.
- 对这些基准计算来评估各种密度函数理论 (DFT) 函数的性能.
- 为化学提供新的基准数据.
主要方法:
- 进行了高水平合集群的计算,其中包括单次和双次激发,以及对三次激发 (CCSD(T)) 的扰动性处理.
- 密度函数理论 (DFT) 的计算使用九个常见函数和两个基础集进行.
- 形成的度,反应能量,振动频率和零点能量被计算和比较.
主要成果:
- CCSD (T) 的结果与形成 (1-2 kJ/mol差异) 度的实验数据非常一致.
- M06-2X功能表现出形成度的最低平均绝对误差 (MAE).
- 对于振动频率和零点能量,SCAN函数的MAE值是最低的,而B2GP-PLYP对反应能量的误差是最小的.
结论:
- 在Si-O-C-H分子的各种性质中,PW6B95功能始终表现良好.
- 对于特定的属性,DFT方法,特别是M06-2X和SCAN,为高级CCSD计算提供了可靠的替代方案.
- 该研究为化学提供了有价值的基准数据,有助于未来的计算研究.
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