Characterization of the High-Pressure Structures and Phase Transformations in SnO2. A Density Functional Theory Study

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• 作者：L. Gracia ; A. Beltr&aacute ; n ; J. André ; s
• 刊名：Journal of Physical Chemistry B
• 出版年：2007
• 出版时间：June 14, 2007
• 年：2007
• 卷：111
• 期：23
• 页码：6479 - 6485
• 全文大小：423K
• 年卷期：v.111,no.23(June 14, 2007)
• ISSN：1520-5207

文摘

Theoretical investigations concerning the high-pressure polymorphs, the equations of state, and the phasetransitions of SnO₂ have been performed using density functional theory at the B3LYP level. Total energycalculations and geometry optimizations have been carried out for all phases involved, and the followingsequence of structural transitions from the rutile-type (P4₂/mnm) driven by pressure has been obtained (thetransition pressure is in parentheses): s/entities/rarr.gif"> CaCl₂-type, Pnnm (12 GPa) s/entities/rarr.gif"> s/gifchars/alpha.gif" BORDER=0>-PbO₂-type, Pbcn (17 GPa) s/entities/rarr.gif">pyrite-type, Pas/entities/thremacr.gif"> (17 GPa) s/entities/rarr.gif"> ZrO₂-type orthorhombic phase I, Pbca (18 GPa) s/entities/rarr.gif"> fluorite-type, Fms/entities/thremacr.gif">m (24GPa) s/entities/rarr.gif"> cotunnite-type orthorhombic phase II, Pnam (33 GPa). The highest bulk modulus values, calculatedby fitting pressure-volume data to the second-order Birch-Murnaghan equation of state, correspond to thecubic pyrite and the fluorite-type phases with values of 293 and 322 GPa, respectively.