在金属-有机框架中的小分子吸附同温的预测
Arpan Kundu1, GiovanniMaria Piccini1, Kaido Sillar1,2
1Institut für Chemie, Humboldt-Universität zu Berlin , Unter den Linden 6, 10099 Berlin, Germany.
Journal of the American Chemical Society
|October 18, 2016
概括
一开始的计算准确地预测了Mg-MOF-74上的CO和N2吸附,从而实现了化学准确性. 这种方法为评估计算化学模型和实验吸附数据提供了可靠的基准.
科学领域:
- 计算化学
- 材料科学
- 物理化学
背景情况:
- 像CPO-27-Mg (Mg-MOF-74) 这样的金属有机框架对气体吸附有希望.
- 对于MOF应用,准确预测吸附性质至关重要.
- 实验吸附数据通常需要理论验证.
研究的目的:
- 在Mg-MOF-74上进行基布斯自由吸附能量的初始计算.
- 开发一种可靠的理论方法来预测MOF中的气体吸附.
- 对计算方法进行比较,并验证实验吸附数据.
主要方法:
- 使用DFT (PBE+D2) 进行结构优化和振动分析的初始计算.
- 混合MP2:(PBE+D2)+ΔCCSD(T) 方法用于精确的电子能量测定.
- 与布拉格-威廉姆斯/朗穆尔模型的整合以及实验场所的可用性.
主要成果:
- 从ab initio数据计算的吸附同热量与实验结果非常一致.
- 对于吉布斯自由能量,达到±1.4kJ/mol的精度,并且在化学精度范围内.
- 为评估DFT+分散方法和实验数据可靠性提供了基准ab initio能量.
结论:
- 提出的 ab initio方法准确地预测了Mg-MOF-74中的气体吸附.
- 这种方法可以作为计算和实验吸附研究的可靠基准.
- 高精度的理论预测对于MOF材料设计和应用评估是有价值的.
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