How Guest Molecules Stabilize the Narrow Pore Phase of Soft Porous Crystals: Structural and Mechanical Properties of MIL-53(Al)⊃H2O

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• 作者：Mingyang Wang ; Xinghua Zhang ; Yunlin Chen ; Dan Li
• 刊名：Journal of Physical Chemistry C
• 出版年：2016
• 出版时间：March 10, 2016
• 年：2016
• 卷：120
• 期：9
• 页码：5059-5066
• 全文大小：453K
• ISSN：1932-7455

文摘

The mechanical properties of a MIL-53(Al) and H₂O composite (MIL-53(Al)⊃H₂O) in the narrow pore (np) phase were addressed using density functional theory. The tensorial analysis of the elastic constants in the np phase provides a further support of adsorption induced stress mechanism of the breathing effect in MIL-53 and the practical mechanical properties of MIL-53(Al) in humidity condition. The adsorption of water molecules in MIL-53(Al) forms a reinforced wine-rack topological structure. The stable structure in the np phase eliminates the high anisotropy and anomalously low Young and shear moduli of the large pore phase. In addition, new soft modes which indicate the evolving path back to the large pore phase were found in the np phase.