Research output: Contribution to journal › Article › peer-review
Aragonite-II and CaCO3-VII : New high-pressure, high-temperature polymorphs of CaCO3. / Gavryushkin, Pavel N.; Martirosyan, Naira S.; Inerbaev, Talgat M. et al.
In: Crystal Growth and Design, Vol. 17, No. 12, 06.12.2017, p. 6291-6296.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Aragonite-II and CaCO3-VII
T2 - New high-pressure, high-temperature polymorphs of CaCO3
AU - Gavryushkin, Pavel N.
AU - Martirosyan, Naira S.
AU - Inerbaev, Talgat M.
AU - Popov, Zakhar I.
AU - Rashchenko, Sergey V.
AU - Likhacheva, Anna Yu
AU - Lobanov, Sergey S.
AU - Goncharov, Alexander F.
AU - Prakapenka, Vitali B.
AU - Litasov, Konstantin D.
N1 - Publisher Copyright: © 2017 American Chemical Society.
PY - 2017/12/6
Y1 - 2017/12/6
N2 - The importance for the global carbon cycle, the P-T phase diagram of CaCO3 has been under extensive investigation since the invention of the high-pressure techniques. However, this study is far from being completed. In the present work, we show the existence of two new highpressure polymorphs of CaCO3. The crystal structure prediction performed here reveals a new polymorph corresponding to distorted aragonite structure and named aragonite-II. In situ diamond anvil cell experiments confirm the presence of aragonite-II at 35 GPa and allow identification of another high-pressure polymorph at 50 GPa, named CaCO3-VII. CaCO3-VII is a structural analogue of CaCO3-P21/c-l, predicted theoretically earlier. The P-T phase diagram obtained based on a quasi-harmonic approximation shows the stability field of CaCO3-VII and aragonite-II at 30-50 GPa and 0- 1200 K. Synthesized earlier in experiments on cold compression of calcite, CaCO3-VI was found to be metastable in the whole pressure-temperature range.
AB - The importance for the global carbon cycle, the P-T phase diagram of CaCO3 has been under extensive investigation since the invention of the high-pressure techniques. However, this study is far from being completed. In the present work, we show the existence of two new highpressure polymorphs of CaCO3. The crystal structure prediction performed here reveals a new polymorph corresponding to distorted aragonite structure and named aragonite-II. In situ diamond anvil cell experiments confirm the presence of aragonite-II at 35 GPa and allow identification of another high-pressure polymorph at 50 GPa, named CaCO3-VII. CaCO3-VII is a structural analogue of CaCO3-P21/c-l, predicted theoretically earlier. The P-T phase diagram obtained based on a quasi-harmonic approximation shows the stability field of CaCO3-VII and aragonite-II at 30-50 GPa and 0- 1200 K. Synthesized earlier in experiments on cold compression of calcite, CaCO3-VI was found to be metastable in the whole pressure-temperature range.
KW - CRYSTAL-STRUCTURE PREDICTION
KW - X-RAY-DIFFRACTION
KW - PHASE-TRANSITIONS
KW - EARTHS MANTLE
KW - PROGRAM
KW - CARBON
KW - COMPRESSIBILITY
KW - REFINEMENT
KW - BEHAVIOR
KW - SYSTEM
UR - http://www.scopus.com/inward/record.url?scp=85042485202&partnerID=8YFLogxK
U2 - 10.1021/acs.cgd.7b00977
DO - 10.1021/acs.cgd.7b00977
M3 - Article
AN - SCOPUS:85042485202
VL - 17
SP - 6291
EP - 6296
JO - Crystal Growth and Design
JF - Crystal Growth and Design
SN - 1528-7483
IS - 12
ER -
ID: 13633374