对水性化物复合物的协调结构和形成常数的集群连续计算
Shaonan Dong1, Xiaodong Jin1, Xiaoxia Hou2
1Department of Forensic Science and Technology, Jiangsu Provincial Engineering Laboratory for Technical and Criminal Inspection of Food, Drug and Environmental Cases, Jiangsu Police Institute, Nanjing 210031, China.
The journal of physical chemistry. A
|September 19, 2025
概括
这项研究揭示了化复合物有利于低协调数,主要是三或四协调. 集群循环方法准确地预测了溶解能量和复杂形成常数 (log K).
科学领域:
- 无机化学 无机化学
- 计算化学计算化学
- 解决方案化学 解决方案化学
背景情况:
- 化复合物在各种化学过程中起着至关重要的作用.
- 了解它们的协调结构和形成常数对于预测化学行为至关重要.
- 准确的热力学数据对于理论和应用化学都至关重要.
研究的目的:
- 研究化物复合物的协调结构和形成常数 (CdXn ((H2O)) ((CN-n)) ((2-n) +).
- 为了比较不同热力学循环方法的精度来计算溶解能量和形成常数.
- 建立一种可靠的方法来预测重金属化物复合物的热力学参数.
主要方法:
- 使用量子化学集群连续模型.
- 对每个复杂类型的24个协调结构的相对能量进行比较.
- 采用不同的热力学循环方法 (集群和单体循环) 来计算溶解能量.
- 应用了"集群大小匹配"方法来准确地确定log K.
主要成果:
- 化复合物主要表现出三或四协调结构.
- 集群循环方法提供了与单体循环相比更接近实验值的溶解能量结果.
- 具有高电子阴性和小半径的化物离子需要更多的水分子来稳定溶解.
- 单质循环通常比集群循环产生更高的log K值.
结论:
- "集群大小匹配"方法可以准确地确定化复合物的log K.
- 热力学循环方法的选择显著影响了溶解能量和log K计算的准确性.
- 这项研究为预测重金属化物复合物的协调结构和热力学参数提供了一个框架.
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