• journal_title：American Mineralogist
• Contributor：Nagayoshi Sata ; Hiroaki Ohfuji ; Kei Hirose ; Hisao Kobayashi ; Yasuo Ohishi ; Naohisa Hirao
• Publisher：Mineralogical Society of America
• Date：2008-
• Format：text/html
• Language：en
• Identifier：10.2138/am.2008.2762
• journal_abbrev：American Mineralogist
• issn：0003-004X
• volume：93
• issue：2-3
• firstpage：492
• section：Letters

FeS exhibits extensive polymorphism at high pressure and temperature. All with NiAs-type (B8) or closely related structures. Here we report a new phase transition from FeS VI to CsCl-type (B2) phase (FeS VII) above 180 GPa based on the synchrotron X-ray diffraction (XRD) measurements. A significant volume reduction by 3.0% was observed at the phase transition, due to an increase in the coordination number from six to eight. Present results suggest that a substantial amount of sulfur may be incorporated into an Fe-Ni alloy with bcc structure in the Earth’s inner core.