Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
Thermodynamics and Equations of State of Iron to 350 GPa and 6000 K. / Dorogokupets, P. I.; Dymshits, A. M.; Litasov, K. D. и др.
в: Scientific Reports, Том 7, 41863, 06.03.2017, стр. 41863.Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
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TY - JOUR
T1 - Thermodynamics and Equations of State of Iron to 350 GPa and 6000 K
AU - Dorogokupets, P. I.
AU - Dymshits, A. M.
AU - Litasov, K. D.
AU - Sokolova, T. S.
PY - 2017/3/6
Y1 - 2017/3/6
N2 - The equations of state for solid (with bcc, fcc, and hcp structures) and liquid phases of Fe were defined via simultaneous optimization of the heat capacity, bulk moduli, thermal expansion, and volume at room and higher temperatures. The calculated triple points at the phase diagram have the following parameters: bcc-fcc-hcp is located at 7.3 GPa and 820 K, bcc-fcc-liquid at 5.2 GPa and 1998 K, and fcc-hcp-liquid at 106.5 GPa and 3787 K. At conditions near the fcc-hcp-liquid triple point, the Clapeyron slope of the fcc-liquid curve is dT/dP = 12.8 K/GPa while the slope of the hcp-liquid curve is higher (dT/dP = 13.7 K/GPa). Therefore, the hcp-liquid curve overlaps the metastable fcc-liquid curve at pressures of about 160 GPa. At high-pressure conditions, the metastable bcc-hcp curve is located inside the fcc-Fe or liquid stability field. The density, adiabatic bulk modulus and P-wave velocity of liquid Fe calculated up to 328.9 GPa at adiabatic temperature conditions started from 5882 K (outer/inner core boundary) were compared to the PREM seismological model. We determined the density deficit of hcp-Fe at the inner core boundary (T = 5882 K and P = 328.9 GPa) to be 4.4%.
AB - The equations of state for solid (with bcc, fcc, and hcp structures) and liquid phases of Fe were defined via simultaneous optimization of the heat capacity, bulk moduli, thermal expansion, and volume at room and higher temperatures. The calculated triple points at the phase diagram have the following parameters: bcc-fcc-hcp is located at 7.3 GPa and 820 K, bcc-fcc-liquid at 5.2 GPa and 1998 K, and fcc-hcp-liquid at 106.5 GPa and 3787 K. At conditions near the fcc-hcp-liquid triple point, the Clapeyron slope of the fcc-liquid curve is dT/dP = 12.8 K/GPa while the slope of the hcp-liquid curve is higher (dT/dP = 13.7 K/GPa). Therefore, the hcp-liquid curve overlaps the metastable fcc-liquid curve at pressures of about 160 GPa. At high-pressure conditions, the metastable bcc-hcp curve is located inside the fcc-Fe or liquid stability field. The density, adiabatic bulk modulus and P-wave velocity of liquid Fe calculated up to 328.9 GPa at adiabatic temperature conditions started from 5882 K (outer/inner core boundary) were compared to the PREM seismological model. We determined the density deficit of hcp-Fe at the inner core boundary (T = 5882 K and P = 328.9 GPa) to be 4.4%.
KW - CRYSTAL-STRUCTURE
KW - EARTHS CORE
KW - GRUNEISEN-PARAMETER
KW - HIGH-PRESSURE IMPLICATIONS
KW - MELTING CURVE
KW - OF-STATE
KW - PHASE-DIAGRAM
KW - SOUND-VELOCITY
KW - THERMAL-EXPANSION
KW - X-RAY-DIFFRACTION
UR - http://www.scopus.com/inward/record.url?scp=85014783779&partnerID=8YFLogxK
U2 - 10.1038/srep41863
DO - 10.1038/srep41863
M3 - Article
C2 - 28262683
AN - SCOPUS:85014783779
VL - 7
SP - 41863
JO - Scientific Reports
JF - Scientific Reports
SN - 2045-2322
M1 - 41863
ER -
ID: 10276089