| Реферат: | eng: The high-pressure behavior of chibaite, newly discovered natural clathrasil isotypical to gas hydrate sII, with ideal formula 136SiO(2)center dot 24X (X = CH4, C2H6, C3H8, C4H10), was studied by Raman spectroscopy up to 7.7 GPa with a diamond anvil cell, using KBr as a pressure transmitting medium. The chibaite structure is preserved throughout the whole pressure range. The deviation from regular shift and appearance of new bands in the lattice spectrum is observed at about 1.2 and 3.5 GPa. As concerns the guest hydrocarbon molecules, the high-frequency shifts of their C-C and C-H bands are almost monotonic within the whole pressure range, showing only slight bends at 1.2 and 3.5 GPa. The FWHMs of stretching C-C and C-H bands demonstrate a high sensitivity to pressure, more pronounced at 1.2 GPa. The obtained data allow to suggest two reversible structural transformations in chibaite at about 1.2 and 3.5 GPa, associated with the distortion of framework cages and corresponding ordering of the guest hydrocarbon molecules. The role of 'guest molecule/host cage' dimensional ratio determining the HP behavior of MEP and MTN clathrasils is discussed. (C) 2015 Elsevier Inc. All rights reserved.
|
| Цитирование: | 1. K. Momma J. Phys. Condens. Matter 26 2014 103203
2. B. Kamb Science 148 1965 232 234
3. H. Gies Z. Krist. 164 1983 247 257
4. M. Tribaudino, A. Artoni, C. Mavris, D. Bersani, P.P. Lottici, and D. Belletti Am. Min. 93 2008 88 94
5. B.A. Kolesov, and C.A. Geiger Am. Min. 88 2003 1364 1368
6. K. Momma, T. Ikeda, K. Nishikubo, N. Takahashi, C. Honma, M. Takada, Y. Furukawa, T. Nagase, and Y. Kudoh Nat. Commun. 2 2011 196
7. K. Knorr, and W. Depmeier J. Solid State Chem. 137 1998 87 93
8. M. Tribaudino, G.D. Gatta, and Y. Lee Microporous Mesoporous Mater. 129 2010 267 273
9. J.S. Tse, D.D. Klug, J.A. Ripmeester, S. Desgreniers, and K. Lagarec Lett. Nat. 369 1994 724 727
10. Y. Liang, F.O. Ogundare, C.R. Miranda, J.K. Christie, and S. Scandolo J. Chem. Phys. 134 2011 074506
11. M. Konnecke, and H. Fuess Zeolites 15 1995 264 269
12. R.P. Gunawardane, H. Gies, and F. Liebau Z. Anorg. Allg. Chem. 546 1987 189 198
13. S.J. Weigel, J.-C. Gabriel, E.G. Puebla, A.M. Bravo, N.J. Henson, L.M. Bull, and A.K. Cheetham J. Am. Chem. Soc. 118 1996 2427 2435
14. A.K. Sum, R.C. Burruss, and E.D. Sloan J. Phys. Chem. B 101 1997 7371 7377
15. S. Subramanian, and E.D. Sloan J. Phys. Chem. B 106 2002 4348 4355
16. S. Subramanian, R.A. Kini, S.F. Dec, and E.D. Sloan Chem. Eng. Sci. 55 2000 1981 1999
17. S. Nakano, M. Moritoki, and K. Ohgaki J. Chem. Eng. Data 44 1999 254 257
18. M. Choukroun, Y. Morizet, and O. Grasset J. Raman Spectrsc. 38 2007 440 451
19. F. Izumi, and K. Momma Solid State Phenom. 130 2007 15 20
20. H.K. Mao, J. Xu, and P.M. Bell J. Geophys. Res. 91 1986 4673 4676
21. B. Chazallon, C. Focsa, J.L. Charlou, C. Bourry, and J.P. Donval Chem. Geol. 244 2007 175 185
22. R.J. Bell, and P. Dean Discuss. Faraday Soc. 50 1970 55 61
23. J. Etchepare, M. Merian, and L. Smetankine J. Chem. Phys. 60 1974 1873 1876
24. D.A. McKeown, M.I. Bell, and C.C. Kim Phys. Rev. B 48 1993 16357
25. S.V. Goryainov, and M.B. Smirnov Eur. J. Mineral. 13 2001 507 519
26. Prabir K. Dutta, B. del Barco, and D.C. Shieh Chem. Phys. Lett. 127 1986 200 204
27. N. Ovsyuk, and S. Goryainov Appl. Phys. Lett. 89 2006 134103-1-4
|