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Density functional theory study of structural stability for gas hydrate |
Ping Guo(郭平), Yi-Long Qiu(邱奕龙), Long-Long Li(李龙龙), Qiang Luo(罗强), Jian-Fei Zhao(赵建飞), Yi-Kun Pan(潘意坤) |
State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China |
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Abstract Using the first-principles method based on the density functional theory (DFT), the structures and electronic properties of different gas hydrates (CO2, CO, CH4, and H2) are investigated within the generalized gradient approximation. The structural stability of methane hydrate is studied in this paper. The results show that the carbon dioxide hydrate is more stable than the other three gas hydrates and its binding energy is -2.36 eV, and that the hydrogen hydrate is less stable and the binding energy is -0.36 eV. Water cages experience repulsion from inner gas molecules, which makes the hydrate structure more stable. Comparing the electronic properties of two kinds of water cages, the energy region of the hydrate with methane is low and the peak is close to the left, indicating that the existence of methane increases the stability of the hydrate structure. Comparing the methane molecule in water cages and a single methane molecule, the energy of electron distribution area of the former is low, showing that the filling of methane enhances the stability of hydrate structure.
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Received: 06 December 2017
Revised: 23 January 2018
Accepted manuscript online:
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PACS:
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31.15.es
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(Applications of density-functional theory (e.g., to electronic structure and stability; defect formation; dielectric properties, susceptibilities; viscoelastic coefficients; Rydberg transition frequencies))
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Fund: Project supported by the National Key Research and Development Program of China (Grant No. 2016YFC0304008). |
Corresponding Authors:
Yi-Long Qiu
E-mail: qiuyl0328@foxmail.com
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Cite this article:
Ping Guo(郭平), Yi-Long Qiu(邱奕龙), Long-Long Li(李龙龙), Qiang Luo(罗强), Jian-Fei Zhao(赵建飞), Yi-Kun Pan(潘意坤) Density functional theory study of structural stability for gas hydrate 2018 Chin. Phys. B 27 043103
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[1] |
Zhao Y S, Xu H W and Yu X H 2009 Physics 38 92(in Chinese)
|
[2] |
Guo P, Pan Y K, Li L L and Tang B 2017 Chin. Phys. B 26 073101
|
[3] |
Du B X, Chen J M, Qian W B and Wang Y 2010 Nat. Gas Explor. Dev. 33 26
|
[4] |
Yan K F, Li X S, Chen Z Y, Li G and Li Z B 2007 Acta Phys. Sin. 56 6727(in Chinese)
|
[5] |
Erfanniya H and Izadkhah S 2016 J. Pet. Sci. Technol. 34 1964
|
[6] |
Chaka A M, Felmy A R and Qafoku O 2016 Chem. Geol. 434 1
|
[7] |
Duan X L, Ren H, Gao G H, Xu J L and Qiu X Q 2014 Petro. Technol. 43 657
|
[8] |
Tang L, Shi R, Su Y and Zhao J 2015 J. Phys. Chem. A 119 10971
|
[9] |
Song J J, Li Y P and Yang Z Y 2012 J. B. Univ. Chem. Technol. 39 36
|
[10] |
Cao X X, Su Y, Zhao J J, Liu C L and Zhou P W 2014 Acta Phys. Sin. 63 1437(in Chinese)
|
[11] |
Xu L Z 2015 "Simulation research and application study on microscopic elastic properties of natural gas hydrate", MS dissertation (Chengdu:the Southwest Petroleum University) (in Chinese)
|
[12] |
Hohenberg P and Kohn W 1964 Phys. Rev 136 B864
|
[13] |
Kohn W and Sham L J 1965 Phys. Rev. 140 A1133
|
[14] |
Kresse G and Joubert D 1999 Phys. Rev. B 59 1758
|
[15] |
McMullan R K and Jeffrey G A 1965 J. Chem. Phys. 42 8
|
[16] |
Perdew J P, Burke K and Ernzerhof M 1996 Phys. Rev. Lett. 77 3865
|
[17] |
Monkhorst H J and Pack J D 1976 Phys. Rev. B 13 5188
|
[18] |
Goldfarb D 1970 Math. Comput. 24 23
|
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