半经验方法的扩展导体式极化连续溶解模型 (CPCM-X)
Marcel Stahn1, Sebastian Ehlert2, Stefan Grimme1
1Mulliken Center of Theoretical Chemistry, 53115 Bonn, Germany.
The journal of physical chemistry. A
|August 11, 2023
概括
我们开发了一种新的计算方法,用于在xTB框架内使用扩展导体样极化连续模型 (CPCM-X) 进行准确的溶解自由能计算. 这种方法显著提高了各种化学系统的准确性,为现有模型提供了更快的替代方案.
科学领域:
- 计算化学计算化学
- 量子力学就是量子力学.
- 物理化学 物理化学
背景情况:
- 准确的溶解自由能计算对于理解化学过程至关重要.
- 现有的半实证量子力学方法往往缺乏足够的准确性来测量溶解效应.
- 极化连续模型 (PCM) 是广泛使用的,但可能是计算要求较高或不太准确.
研究的目的:
- 开发一种新的,准确的,计算效率高的方法来计算溶解自由能量.
- 将域分解导体样选模型 (ddCOSMO) 集成到扩展密结 (xTB) 框架中.
- 改进 xTB 程序包中现有的解决模型.
主要方法:
- 开发了用于xTB的扩展导体样极化连续模型 (CPCM-X).
- 纳入了计算效率高的域分解导体样选模型 (ddCOSMO).
- 使用一种后处理方法,引用已建立的溶解模型 (COSMO-RS,SMD).
主要成果:
- CPCM-X在各种基准中表现出高准确度,包括水化和非水性自由能量.
- 与当前的xTB方法相比,高分子关联反应的精度提高了40%.
- 这种新方法与更高级别的DFT模型 (COSMO-RS,SMD) 的准确性相匹配,同时速度快100倍以上.
结论:
- CPCM-X方法为xTB的精确和高效的溶解自由能量计算提供了显著的进步.
- 这种方法广泛适用于各种溶剂环境中的中性和带电物种.
- 开发的模型可以在xTB程序中用于各种计算化学应用.
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