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Fe(CO3)2 crystallizes in the orthorhombic Cccm space group. The structure is zero-dimensional and consists of sixteen carbon dioxide molecules and eight iron dihydroxide molecules.
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
In order to predict what biomarkers could be used on Mars, several biomarkers, or key signatures, of extinct life on earth are identified. Some of these biomarkers which may be applicable to Mars include reduced carbon and nitrogen compounds, CO3(2-), SO4(2-), NO3(-), Mg, Mn, Fe, and the isotopic ratios of C, N, and S. It is suggested that a fully equipped Mars rover might be able to perform analyses to measure most of these biomarkers while on the Martian surface.
A deep ultraviolet (DUV) Raman and fluorescence instrument is a surface standoff instrument mounted on the robotic arm of the Mars 2020 (M2020) rover Perseverance, and it is a key element of the Scanning Habitable Environments with Luminescence for Organics and Chemicals (SHERLOC) investigation [1]. Measurement and science objectives include mineralogical and organic images (~100 μm/pixel) that map sub-millimeter spatial distributions and characterization of primary and secondary minerals, potential organics, and their interaction/alteration products. The results of data analysis pertain to understanding igneous and alteration processes on Mars through time, assessing habitability, evidencing in situ biosignatures, and, along with results from other Perseverance instruments, selecting samples to cache for Mars sample return. Acceptance of the SHERLOC investigation for the NASA M2020 mission [2] created a need for Mars-relevant DUV Raman spectra, particularly for inorganic materials [e.g., 3, 4]. As reported previously [e.g., 4, 5], phases with Fe cations as essential elements (e.g., siderite (FeCO3) and ankerite (FeCa(CO3)2) for carbonates) significantly hinder detection by DUV Raman because of intense absorption of incident and scattered DUV laser radiation by Fe cations. We report here the relative detectability of carbonates (Mg,Ca,Fe,Mn)CO3 by DUV Raman using a SHERLOC analog laboratory instrument.
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
FeH2(CO3)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded in an octahedral geometry to six O2- atoms. There are a spread of Fe–O bond distances ranging from 2.04–2.06 Å. In the second Fe2+ site, Fe2+ is bonded in an octahedral geometry to six O2- atoms. There are a spread of Fe–O bond distances ranging from 1.81–2.09 Å. There are two inequivalent C4+ sites. In the first C4+ site, C4+ is bonded in a trigonal planar geometry to one H1+ and two O2- atoms. The C–H bond length is 1.10 Å. Both C–O bond lengths are 1.27 Å. In the second C4+ site, C4+ is bonded in a trigonal planar geometry to one H1+ and two O2- atoms. The C–H bond length is 1.11 Å. There is one shorter (1.26 Å) and one longer (1.27 Å) C–O bond length. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one C4+ atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one C4+ atom. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Fe2+ and one C4+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one Fe2+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one Fe2+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one Fe2+ and one C4+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Fe2+ and one C4+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Fe2+ and one C4+ atom.
Two novel ternary compounds are noted in the present study of 1000 C solid-state equilibria in the Fe-Co-P-O system's Fe2O3-FePO4-Co3(Po4)2-CoO region: CoFe(PO4)O, which undergoes incongruent melting at 1130 C, and Co3Fe4(PO4)6, whose incongruent melting occurs at 1080 C. The liquidus behavior-related consequences of rapidly solidified cobalt ferrite formation from cobalt ferrite-phosphate melts are discussed with a view to spinel formation. It is suggested that quenching from within the spinel-plus-liquid region may furnish an alternative to quenching a homogeneous melt.
MgFe(CO3)2 is Calcite-derived structured and crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Mg2+ is bonded to six equivalent O2- atoms to form MgO6 octahedra that share corners with six equivalent FeO6 octahedra. The corner-sharing octahedral tilt angles are 59°. All Mg–O bond lengths are 2.12 Å. Fe2+ is bonded to six equivalent O2- atoms to form FeO6 octahedra that share corners with six equivalent MgO6 octahedra. The corner-sharing octahedral tilt angles are 59°. All Fe–O bond lengths are 2.18 Å. C4+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All C–O bond lengths are 1.30 Å. O2- is bonded in a distorted trigonal planar geometry to one Mg2+, one Fe2+, and one C4+ atom.