TY  - JOUR
AU  - Bayarjargal, Lkhamsuren
AU  - Spahr, Dominik
AU  - Bykova, Elena
AU  - Wang, Yu
AU  - Giordano, Nico
AU  - Milman, Victor
AU  - Winkler, Björn
TI  - High-Pressure Synthesis of an Iron Carbonate, Fe<sub>2</sub>[CO<sub>3</sub>]<sub>3</sub>
JO  - Inorganic chemistry
VL  - 63
IS  - 45
SN  - 0020-1669
CY  - Washington, DC
PB  - American Chemical Society
M1  - PUBDB-2025-00246
SP  - 21637-21644
PY  - 2024
N1  - DFG (projects BA4020 and WI1232) Waiting for fulltext 
AB  - We synthesized an iron carbonate, Fe<sub>2</sub><sup>3+</sup>[CO<sub>3</sub>]<sub>3</sub>, by reacting Fe<sub>2</sub>O<sub>3</sub> with CO<sub>2</sub> at high temperatures and pressures of approximately 33(3) GPa. The structure was solved by single-crystal X-ray diffraction. Full geometry optimizations based on density functional theory reproduced the crystal structure. This compound crystallizes in the monoclinic space group P2<sub>1</sub>/n. The characteristic feature of the Fe<sub>2</sub><sup>3+</sup>[CO<sub>3</sub>]<sub>3</sub>-structure is the presence of 7- and 8-fold coordinated trivalent cations and noncoplanar [CO<sub>3</sub>]<sup>2–</sup> groups. The normals of the [CO<sub>3</sub>]<sup>2–</sup> groups point in four different directions. The bulk modulus of Fe<sub>2</sub>[CO<sub>3</sub>]<sub>3</sub> is K<sub>0</sub> = 138(34)GPa (when K<sub>p</sub> is fixed to 4). While previous studies have shown that siderite, Fe<sup>2+</sup>CO<sub>3</sub> decomposes at lower mantle conditions (pressures between 20 and 50 GPa and high temperatures), Fe<sub>2</sub><sup>3+</sup>[CO<sub>3</sub>]<sub>3</sub> may be stable around 33(3) GPa and up to 2600(300) K. Iron carbonates with Fe<sup>3+</sup> are therefore more likely present at lower mantle conditions than carbonates containing Fe<sup>2+</sup>.
LB  - PUB:(DE-HGF)16
C6  - pmid:39466183
UR  - <Go to ISI:>//WOS:001344019200001
DO  - DOI:10.1021/acs.inorgchem.4c03177
UR  - https://bib-pubdb1.desy.de/record/622208
ER  -