Phase transitions of sulfur under high-pressure and high-temperature condition
Project/Area Number |
15540456
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Petrology/Mineralogy/Science of ore deposit
|
Research Institution | Tohoku University |
Principal Investigator |
KUSABA Keiji Tohoku University, Institute for Materials Research, Research Associate, 金属材料研究所, 助手 (60186385)
|
Project Period (FY) |
2003 – 2004
|
Project Status |
Completed (Fiscal Year 2004)
|
Budget Amount *help |
¥2,600,000 (Direct Cost: ¥2,600,000)
Fiscal Year 2004: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 2003: ¥1,900,000 (Direct Cost: ¥1,900,000)
|
Keywords | sulfur / multi-anvil type apparatus / synchrotron radiation / sintered diamond / phase transition / crystal structure / compression curve / P-T phase diagram / 高温高圧 |
Research Abstract |
High-pressure and high-temperature behavior of sulfur was directly observed, using a combination of multi-anvil type high-pressure apparatus"MAX80"and synchrotron radiation. Observable pressure and temperature range was expanded up to 17 GPa and 900℃ by using sintered diamond anvils. Three high-pressure phases were found in the range. All high-pressure phases were unquenchable at ambient condition. Crystal structures of the high-pressure phases were determined from their X-ray powder diffraction patterns. The high-pressure phase 1 has a hexagonal cell, in which sulfur atoms form helical chains. The high-pressure phase 2 has another hexagonal cell and the structure is built up of cyclic molecule of S_6. The high-pressure phase 3 contains another helical chains in a tetragonal cell. Compression behaviors of all high-pressure phases and the low-pressure phase were observed at room temperature condition. An anisotropic compression behavior was found in the case of the high-pressure phase 2. The pressure and temperature phase diagram of sulfur was also determined, based on the in-situ observations.
|
Report
(3 results)
Research Products
(10 results)