Simulating the Dehydroxylation Reaction in Smectite Models by Car–Parrinello-like–Born–Oppenheimer Molecular Dynamics and Metadynamics

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• 作者：Daniel Muñoz-SantiburcioAlfonso Hernández-Laguna ; Claro Ignacio Sainz-Díaz
• 刊名：Journal of Physical Chemistry C
• 出版年：2016
• 出版时间：December 15, 2016
• 年：2016
• 卷：120
• 期：49
• 页码：28186-28192
• 全文大小：507K
• ISSN：1932-7455

文摘

The first step of a dehydroxylation reaction of a medium-charged dioctahedral smectite model is studied by means of ab initio molecular dynamics simulations. Combining the Car–Parrinello-like–Born–Oppenheimer molecular dynamics method with metadynamics, we find two previously proposed mechanisms (dubbed on-site and cross). We confirm the existence of an intermediate state where the tetrahedral structure is deformed, a feature that is also present in the final (semidehydroxylate) state of this reaction. This shows that the thermal transformations of phyllosilicates are more complex than often assumed, which will be relevant when elucidating the mechanisms of other transformations of these materials.