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Raman spectroscopy and x-ray diffraction of sp3 CaC O3 at lower mantle pressures. / Lobanov, Sergey S.; Dong, Xiao; Martirosyan, Naira S. et al.

In: Physical Review B, Vol. 96, No. 10, 104101, 01.09.2017.

Research output: Contribution to journal › Article › peer-review

Harvard

Lobanov, SS, Dong, X, Martirosyan, NS, Samtsevich, AI, Stevanovic, V, Gavryushkin, PN, Litasov, KD, Greenberg, E, Prakapenka, VB, Oganov, AR & Goncharov, AF 2017, 'Raman spectroscopy and x-ray diffraction of sp3 CaC O3 at lower mantle pressures', Physical Review B, vol. 96, no. 10, 104101. https://doi.org/10.1103/PhysRevB.96.104101

APA

Lobanov, S. S., Dong, X., Martirosyan, N. S., Samtsevich, A. I., Stevanovic, V., Gavryushkin, P. N., Litasov, K. D., Greenberg, E., Prakapenka, V. B., Oganov, A. R., & Goncharov, A. F. (2017). Raman spectroscopy and x-ray diffraction of sp3 CaC O3 at lower mantle pressures. Physical Review B, 96(10), [104101]. https://doi.org/10.1103/PhysRevB.96.104101

Vancouver

Lobanov SS, Dong X, Martirosyan NS, Samtsevich AI, Stevanovic V, Gavryushkin PN et al. Raman spectroscopy and x-ray diffraction of sp3 CaC O3 at lower mantle pressures. Physical Review B. 2017 Sept 1;96(10):104101. doi: 10.1103/PhysRevB.96.104101

Author

Lobanov, Sergey S. ; Dong, Xiao ; Martirosyan, Naira S. et al. / Raman spectroscopy and x-ray diffraction of sp3 CaC O3 at lower mantle pressures. In: Physical Review B. 2017 ; Vol. 96, No. 10.

BibTeX

@article{45b9dc0710fd40a0919dad1bfd433f48,
title = "Raman spectroscopy and x-ray diffraction of sp3 CaC O3 at lower mantle pressures",
abstract = "The exceptional ability of carbon to form sp2 and sp3 bonding states leads to a great structural and chemical diversity of carbon-bearing phases at nonambient conditions. Here we use laser-heated diamond-anvil cells combined with synchrotron x-ray diffraction, Raman spectroscopy, and first-principles calculations to explore phase transitions in CaCO3 at P>40GPa. We find that postaragonite CaCO3 transforms to the previously predicted P21/cCaCO3 with sp3-hybridized carbon at 105 GPa (∼30GPa higher than the theoretically predicted crossover pressure). The lowest-enthalpy transition path to P21/cCaCO3 includes reoccurring sp2 and sp3CaCO3 intermediate phases and transition states, as revealed by our variable-cell nudged-elastic-band simulation. Raman spectra of P21/cCaCO3 show an intense band at 1025cm-1, which we assign to the symmetric C-O stretching vibration based on empirical and first-principles calculations. This Raman band has a frequency that is ∼20% lower than the symmetric C-O stretching in sp2CaCO3 due to the C-O bond length increase across the sp2-sp3 transition and can be used as a fingerprint of tetrahedrally coordinated carbon in other carbonates.",
keywords = "EARTHS LOWER MANTLE, CRYSTAL-STRUCTURE PREDICTION, ELASTIC BAND METHOD, CALCITE-III, CARBON, TRANSITION, PHASE, ARAGONITE, MAGNESITE, DOLOMITE",
author = "Lobanov, {Sergey S.} and Xiao Dong and Martirosyan, {Naira S.} and Samtsevich, {Artem I.} and Vladan Stevanovic and Gavryushkin, {Pavel N.} and Litasov, {Konstantin D.} and Eran Greenberg and Prakapenka, {Vitali B.} and Oganov, {Artem R.} and Goncharov, {Alexander F.}",
note = "Publisher Copyright: {\textcopyright} 2017 American Physical Society.",
year = "2017",
month = sep,
day = "1",
doi = "10.1103/PhysRevB.96.104101",
language = "English",
volume = "96",
journal = "Physical Review B",
issn = "2469-9950",
publisher = "American Physical Society",
number = "10",

}

RIS

TY - JOUR

T1 - Raman spectroscopy and x-ray diffraction of sp3 CaC O3 at lower mantle pressures

AU - Lobanov, Sergey S.

AU - Dong, Xiao

AU - Martirosyan, Naira S.

AU - Samtsevich, Artem I.

AU - Stevanovic, Vladan

AU - Gavryushkin, Pavel N.

AU - Litasov, Konstantin D.

AU - Greenberg, Eran

AU - Prakapenka, Vitali B.

AU - Oganov, Artem R.

AU - Goncharov, Alexander F.

N1 - Publisher Copyright: © 2017 American Physical Society.

PY - 2017/9/1

Y1 - 2017/9/1

N2 - The exceptional ability of carbon to form sp2 and sp3 bonding states leads to a great structural and chemical diversity of carbon-bearing phases at nonambient conditions. Here we use laser-heated diamond-anvil cells combined with synchrotron x-ray diffraction, Raman spectroscopy, and first-principles calculations to explore phase transitions in CaCO3 at P>40GPa. We find that postaragonite CaCO3 transforms to the previously predicted P21/cCaCO3 with sp3-hybridized carbon at 105 GPa (∼30GPa higher than the theoretically predicted crossover pressure). The lowest-enthalpy transition path to P21/cCaCO3 includes reoccurring sp2 and sp3CaCO3 intermediate phases and transition states, as revealed by our variable-cell nudged-elastic-band simulation. Raman spectra of P21/cCaCO3 show an intense band at 1025cm-1, which we assign to the symmetric C-O stretching vibration based on empirical and first-principles calculations. This Raman band has a frequency that is ∼20% lower than the symmetric C-O stretching in sp2CaCO3 due to the C-O bond length increase across the sp2-sp3 transition and can be used as a fingerprint of tetrahedrally coordinated carbon in other carbonates.

AB - The exceptional ability of carbon to form sp2 and sp3 bonding states leads to a great structural and chemical diversity of carbon-bearing phases at nonambient conditions. Here we use laser-heated diamond-anvil cells combined with synchrotron x-ray diffraction, Raman spectroscopy, and first-principles calculations to explore phase transitions in CaCO3 at P>40GPa. We find that postaragonite CaCO3 transforms to the previously predicted P21/cCaCO3 with sp3-hybridized carbon at 105 GPa (∼30GPa higher than the theoretically predicted crossover pressure). The lowest-enthalpy transition path to P21/cCaCO3 includes reoccurring sp2 and sp3CaCO3 intermediate phases and transition states, as revealed by our variable-cell nudged-elastic-band simulation. Raman spectra of P21/cCaCO3 show an intense band at 1025cm-1, which we assign to the symmetric C-O stretching vibration based on empirical and first-principles calculations. This Raman band has a frequency that is ∼20% lower than the symmetric C-O stretching in sp2CaCO3 due to the C-O bond length increase across the sp2-sp3 transition and can be used as a fingerprint of tetrahedrally coordinated carbon in other carbonates.

KW - EARTHS LOWER MANTLE

KW - CRYSTAL-STRUCTURE PREDICTION

KW - ELASTIC BAND METHOD

KW - CALCITE-III

KW - CARBON

KW - TRANSITION

KW - PHASE

KW - ARAGONITE

KW - MAGNESITE

KW - DOLOMITE

UR - http://www.scopus.com/inward/record.url?scp=85029956113&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.96.104101

DO - 10.1103/PhysRevB.96.104101

M3 - Article

AN - SCOPUS:85029956113

VL - 96

JO - Physical Review B

JF - Physical Review B

SN - 2469-9950

IS - 10

M1 - 104101

ER -

ID: 9905977