循环合作性贡献决定了分子团中的键强度
Ayush Shivhare1, Bharti Dehariya1, Shridhar R Gadre2
1Department of Chemistry, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar-470003, India. milind.deshmukh@gmail.com.
Physical chemistry chemical physics : PCCP
|January 29, 2025
概括
这项研究验证了一种用于计算分子团中键 (HB) 能量的新方法. 该方法准确地估计了各种分子的HB能量,为循环合作性提供了洞察力.
科学领域:
- 计算化学的计算化学
- 物理化学 物理化学
- 分子相互作用 分子相互作用
背景情况:
- 键 (HBs) 在分子中至关重要,但在复杂网络中准确计算它们的能量是具有挑战性的.
- 之前的研究提出了一种方法,使用循环结构的合作性贡献 (CC) 来估计水中的HB能量.
- 这种方法显示了计算 (ESynergeticHB) 和实际集群HB能量 (EclusterHB) 之间的良好一致.
研究的目的:
- 测试HB能量计算方法在多种分子的普遍适用性.
- 评估方法对不同强度 (1-19 kcal mol-1) 的HBs的准确性.
- 探索HB能源估计和周期性合作模式之间的关系.
主要方法:
- 该研究采用分子定制方法 (MTA) 来估计循环HB网络中的CC.
- 将CCs的总和添加到相应的孤立二元的HB能量中,以获得协同HB能量 (ESynergeticHB).
- 该方法应用于各种分子,包括氨,硫化,以及与水,甲醇和化混合的系统.
主要成果:
- 在所有测试的分子中,HB能量计算方法表现出高精度.
- 计算的 (ESynergeticHB) 和实际的集群HB能量 (EclusterHB) 之间的绝对差异始终低于0.5kcal mol-1.
- 该方法成功地将HB能量估计与观察到的周期性合作性相关联:完全周期性合作性 (FCC),部分周期性合作性 (PCC) 和反合作性 (AC).
结论:
- 经过验证的方法提供了一种强大而准确的方法来确定各种分子团中的键能量.
- 这种方法为了解化学系统中的分子间力量和网络动态提供了有价值的工具.
- 这些发现扩大了基于MTA的方法的实用性,并为基于合作的HB能源分析提供了定性指导方针.
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