Compression of Silver Sulfide: X-ray Diffraction Measurements and Total-Energy Calculations

详细信息    查看全文

• 作者：David Santamarı ; ́ ; a-P茅rez ; Miriam Marqu茅s ; Raquel Chuli谩-Jord谩n ; Jos茅 M. Menendez ; Oscar Gomis ; Javier Ruiz-Fuertes ; Juan A. Sans ; Daniel Errandonea ; Jos茅 M. Recio
• 刊名：Inorganic Chemistry
• 出版年：2012
• 出版时间：May 7, 2012
• 年：2012
• 卷：51
• 期：9
• 页码：5289-5298
• 全文大小：568K
• 年卷期：v.51,no.9(May 7, 2012)
• ISSN：1520-510X

文摘

Angle-dispersive X-ray diffraction measurements have been performed in acanthite, Ag₂S, up to 18 GPa in order to investigate its high-pressure structural behavior. They have been complemented by ab initio electronic structure calculations. From our experimental data, we have determined that two different high-pressure phase transitions take place at 5 and 10.5 GPa. The first pressure-induced transition is from the initial anti-PbCl₂-like monoclinic structure (space group P2₁/n) to an orthorhombic Ag₂Se-type structure (space group P2₁2₁2₁). The compressibility of the lattice parameters and the equation of state of both phases have been determined. A second phase transition to a P2₁/n phase has been found, which is a slight modification of the low-pressure structure (Co₂Si-related structure). The initial monoclinic phase was fully recovered after decompression. Density functional and, in particular, GGA+U calculations present an overall good agreement with the experimental results in terms of the high-pressure sequence, cell parameters, and their evolution with pressure.