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论文类型： 期刊论文

发表时间： 2012-07-30

发表刊物： INTERNATIONAL JOURNAL OF MODERN PHYSICS B

收录刊物： SCIE

卷号： 26

期号： 19

ISSN号： 0217-9792

关键字： First-principles; Mg2SiO4; elastic properties; water; high pressure

摘要： The hydration effects of water on the high-pressure elastic properties of three Mg2SiO4 polymorphs have been investigated using first-principles simulation density functional theory. The effect of water incorporation was simulated by considering Mg2SiO4 crystals with water contents of 0, 1.65 and 3.3 wt%. With increasing water content, the calculated bulk/shear modulus and sound velocities decrease and their pressure derivatives tend to increase. Thus the hydration effect becomes less obvious at higher pressure. The bulk velocity contrasts from olivine to wadsleyite and from wadsleyite to ringwoodite are found to decrease after water incorporation. Our theoretical results indicate that water content and partition around the phase boundaries have profound impact on the structural and seismic properties of the mantle.