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电子结构理论方法,热力学和隐性溶解校正对有机碳酸盐构造和结合能量的影响

Alexander S Ryzhako^1,2, Anna A Tuma^1,3, Arseniy A Otlyotov¹

¹N.N. Semenov Federal Research Center for Chemical Physics RAS, Moscow, Russian Federation.

Journal of computational chemistry

|September 17, 2024

概括

有机碳酸盐的精确形态能量需要先进的GFNn-xTB方法,而不是标准的力场或半实证模型. 溶解显著影响能量,而热力学校正提供适度的影响.

科学领域:

计算化学的计算化学
分子建模分子建模
物理化学物理化学

背景情况:

有机碳酸盐在各种化学应用中至关重要.
准确地预测它们的构造和结合能量对于理解它们的行为至关重要.
现有的计算方法在复制实验或高级理论数据的能力上有所不同.

研究的目的:

评估不同计算方法对有机碳酸盐集群的构造和结合能量的影响.
确定可靠的方法来预测有机碳酸盐的稳定性和相互作用.
评估热力学校正和溶解模型的影响.

主要方法:

测试各种力场 (GFN-FF,GAFF,MMFF94) 和半实证方法 (PM3,AM1,RM1,PM6,PM6-D3,PM6-D3H4,PM7) 的方法.
使用紧固结合的GFNn-xTB方法进行比较.
结合气相热力学校正和连续溶解模型.
将结果与参考RI-SCS-MP2形态能量进行比较.

主要成果:

标准的力场和半实证方法无法再现参考形态能量.
GFNn-xTB 方法提供了更现实的 conformational 能量,足以丢弃不稳定的 conformers.
热力学校正对气相稳定性排名产生了适度的影响.
连续性溶解,特别是使用吉布斯自由能量校正,显著减少了构造能量的传播.
集群结合能量显示出高度依赖振动热化学近似值.

结论:

建议使用GFNn-xTB方法进行精确的有机碳酸盐构造分析.
溶解效应至关重要,应在计算研究中仔细考虑.
振动热化学近似显著影响约束能量的计算.

关键词:

计算化学方法测试测试方法测试合规性分析是一种分析.有机碳酸盐集群有机碳酸盐集群溶剂的作用是溶剂的作用.热力学纠正的热力学纠正.

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