Decomposition dynamics of dodecahedron and tetrakaidecahedron structures in methane hydrate by molecular simulations

• Published in: Asia-Pacific journal of chemical engineering 2020-03, Vol.15 (2), p.n/a
• Main Authors: Li, Jia, Liang, Zhenju, Wang, Zhaoliang, Meng, Guangfan
• Format: Article
• Language: English
• Subjects: cage‐like structure; decomposition characteristics; interaction energy; methane hydrate; molecular dynamics simulation; vibration density of states
• ISSN: 1932-2135; 1932-2143
• DOI: 10.1002/apj.2412

The decomposition of dodecahedron and tetrakaidecahedron in methane hydrate is studied by molecular dynamics simulation. For each single cage‐like structure, the decomposition is divided into three stages according to the different characteristics in each stage. The interaction from each part of the system to the single cage‐like structure is analyzed. The feature of hydrogen bond and the transformation in vibration density of states of oxygen during decomposition are investigated. The influences of heat flow disturbance and different initial temperature are estimated. The results show that for two different size structures, the time required by each stage is different. However, the percentage of residual hydrogen bond basically keeps the same. When decomposing, the total interaction energy to the cage‐like structure increases and the vibration density of states of oxygen in cage‐like structure converts more similar to that in liquid water. It suggests that heat flow disturbances and higher initial temperature may exacerbate the decomposition of single cage‐like structure.