%0 Journal Article
%A Bayarjargal, Lkhamsuren
%A Spahr, Dominik
%A Bykova, Elena
%A Wang, Yu
%A Giordano, Nico
%A Milman, Victor
%A Winkler, Björn
%T High-Pressure Synthesis of an Iron Carbonate, Fe<sub>2</sub>[CO<sub>3</sub>]<sub>3</sub>
%J Inorganic chemistry
%V 63
%N 45
%@ 0020-1669
%C Washington, DC
%I American Chemical Society
%M PUBDB-2025-00246
%P 21637-21644
%D 2024
%Z DFG (projects BA4020 and WI1232) Waiting for fulltext 
%X 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>.
%F PUB:(DE-HGF)16
%9 Journal Article
%$ pmid:39466183
%U <Go to ISI:>//WOS:001344019200001
%R 10.1021/acs.inorgchem.4c03177
%U https://bib-pubdb1.desy.de/record/622208