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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
(Fe(SO4)2)2N2 crystallizes in the trigonal P321 space group. The structure is two-dimensional and consists of one ammonia molecule and one Fe(SO4)2 sheet oriented in the (0, 0, 1) direction. In the Fe(SO4)2 sheet, Fe3+ is bonded to six equivalent O2- atoms to form distorted FeO6 octahedra that share corners with six equivalent SO4 tetrahedra. All Fe–O bond lengths are 2.02 Å. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three equivalent FeO6 octahedra. The corner-sharing octahedral tilt angles are 35°. There is one shorter (1.45 Å) and three longer (1.50 Å) S–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one S6+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe3+ and one S6+ atom.
Fe(H2O)6(CN3H6)2(SO4)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four guanidinium molecules, two iron hexahydrate molecules, and four sulfuric acid molecules.
Fe(H2O)6Fe(H2O)8(SO4)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of two iron hexahydrate molecules, two iron octahydrate molecules, and four sulfuric acid 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
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
FeTl(SO4)2 crystallizes in the trigonal P321 space group. The structure is three-dimensional. Fe3+ is bonded to six equivalent O2- atoms to form distorted FeO6 pentagonal pyramids that share corners with six equivalent SO4 tetrahedra and faces with two equivalent TlO12 cuboctahedra. All Fe–O bond lengths are 2.04 Å. Tl1+ is bonded to twelve O2- atoms to form distorted TlO12 cuboctahedra that share edges with six equivalent TlO12 cuboctahedra, edges with six equivalent SO4 tetrahedra, and faces with two equivalent FeO6 pentagonal pyramids. There are six shorter (3.05 Å) and six longer (3.44 Å) Tl–O bond lengths. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three equivalent FeO6 pentagonal pyramids and edges with three equivalent TlO12 cuboctahedra. There is one shorter (1.47 Å) and three longer (1.49 Å) S–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe3+, one Tl1+, and one S6+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to three equivalent Tl1+ and one S6+ atom.
RbFe(SO4)2 crystallizes in the trigonal P321 space group. The structure is three-dimensional. Rb1+ is bonded to twelve O2- atoms to form distorted RbO12 cuboctahedra that share edges with six equivalent RbO12 cuboctahedra, edges with six equivalent SO4 tetrahedra, and faces with two equivalent FeO6 octahedra. There are six shorter (3.03 Å) and six longer (3.40 Å) Rb–O bond lengths. Fe3+ is bonded to six equivalent O2- atoms to form distorted FeO6 octahedra that share corners with six equivalent SO4 tetrahedra and faces with two equivalent RbO12 cuboctahedra. All Fe–O bond lengths are 2.00 Å. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three equivalent FeO6 octahedra and edges with three equivalent RbO12 cuboctahedra. The corner-sharing octahedral tilt angles are 35°. There is one shorter (1.47 Å) and three longer (1.49 Å) S–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Rb1+, one Fe3+, and one S6+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent Rb1+ and one S6+ atom.
Li1.0Fe(SO4)2 crystallizes in the monoclinic Pc space group. The structure is three-dimensional. there are four inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 1.90–2.52 Å. In the second Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 1.92–2.41 Å. In the third Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 1.95–2.60 Å. In the fourth Li1+ site, Li1+ is bonded to six O2- atoms to form distorted LiO6 pentagonal pyramids that share corners with four FeO6 octahedra, corners with two SO4 tetrahedra, and edges with two SO4 tetrahedra. The corner-sharing octahedra tilt angles range from 48–59°. There are a spread of Li–O bond distances ranging from 1.99–2.29 Å. There are four inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share a cornercorner with one LiO6 pentagonal pyramid and corners with six SO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.98–2.12 Å. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share a cornercorner with one LiO6 pentagonal pyramid and corners with six SO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.98–2.11 Å. In the third Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six SO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.03–2.09 Å. In the fourth Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent LiO6 pentagonal pyramids and corners with six SO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.02–2.08 Å. There are eight inequivalent S6+ sites. In the first S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three FeO6 octahedra and a cornercorner with one LiO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 37–46°. There are a spread of S–O bond distances ranging from 1.47–1.51 Å. In the second S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three FeO6 octahedra and an edgeedge with one LiO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 47–48°. There are a spread of S–O bond distances ranging from 1.44–1.52 Å. In the third S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three FeO6 octahedra. The corner-sharing octahedra tilt angles range from 44–46°. There are a spread of S–O bond distances ranging from 1.45–1.50 Å. In the fourth S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three FeO6 octahedra. The corner-sharing octahedra tilt angles range from 42–49°. There are a spread of S–O bond distances ranging from 1.43–1.53 Å. In the fifth S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three FeO6 octahedra. The corner-sharing octahedra tilt angles range from 39–48°. There are a spread of S–O bond distances ranging from 1.44–1.53 Å. In the sixth S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three FeO6 octahedra and a cornercorner with one LiO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 46–50°. There are a spread of S–O bond distances ranging from 1.45–1.51 Å. In the seventh S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three FeO6 octahedra. The corner-sharing octahedra tilt angles range from 47–48°. There are a spread of S–O bond distances ranging from 1.45–1.52 Å. In the eighth S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three FeO6 octahedra and an edgeedge with one LiO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 38–47°. There are a spread of S–O bond distances ranging from 1.45–1.52 Å. There are thirty-two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe3+, and one S6+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one Li1+ and one S6+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe3+, and one S6+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Fe3+, and one S6+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe3+, and one S6+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Fe3+ and one S6+ atom. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe3+ and one S6+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Li1+ and one S6+ atom. In the ninth O2- site, O2- is bonded in a bent 120 degrees geometry to one Li1+ and one S6+ atom. In the tenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Fe3+ and one S6+ atom. In the eleventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Fe3+ and one S6+ atom. In the twelfth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Fe3+ and one S6+ atom. In the thirteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Fe3+, and one S6+ atom. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe3+, and one S6+ atom. In the fifteenth O2- site, O2- is bonded in a bent 120 degrees geometry to one Li1+ and one S6+ atom. In the sixteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Fe3+ and one S6+ atom. In the seventeenth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe3+, and one S6+ atom. In the eighteenth O2- site, O2- is bonded in a single-bond geometry to one S6+ atom. In the nineteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe3+, and one S6+ atom. In the twentieth O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe3+ and one S6+ atom. In the twenty-first O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe3+, and one S6+ atom. In the twenty-second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Fe3+, and one S6+ atom. In the twenty-third O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe3+, and one S6+ atom. In the twenty-fourth O2- site, O2- is bonded in a 2-coordinate geometry to two Li1+ and one S6+ atom. In the twenty-fifth O2- site, O2- is bonded in a bent 120 degrees geometry to one Li1+ and one S6+ atom. In the twenty-sixth O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe3+ and one S6+ atom. In the twenty-seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Fe3+ and one S6+ atom. In the twenty-eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe3+, and one S6+ atom. In the twenty-ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Fe3+, and one S6+ atom. In the thirtieth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe3+, and one S6+ atom. In the thirty-first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Li1+ and one S6+ atom. In the thirty-second O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Fe3+, and one S6+ atom.
NaFe(SO4)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Na1+ is bonded in a distorted hexagonal planar geometry to six O2- atoms. There are two shorter (2.45 Å) and four longer (2.66 Å) Na–O bond lengths. Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six equivalent SO4 tetrahedra. There are two shorter (1.99 Å) and four longer (2.04 Å) Fe–O bond lengths. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 36–45°. There are a spread of S–O bond distances ranging from 1.45–1.51 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe3+ and one S6+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+ and one S6+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe3+, and one S6+ atom.
Fe(H2O)6(FeH8(SO6)2)2 crystallizes in the triclinic P-1 space group. The structure is two-dimensional and consists of one iron hexahydrate molecule and one FeH8(SO6)2 sheet oriented in the (0, 0, 1) direction. In the FeH8(SO6)2 sheet, Fe+2.67+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two SO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 1.96–2.09 Å. There are eight inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.68 Å) H–O bond length. In the second H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.65 Å) H–O bond length. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the sixth H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.65 Å) H–O bond length. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.72 Å) H–O bond length. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are two inequivalent S6+ sites. In the first S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share a cornercorner with one FeO6 octahedra. The corner-sharing octahedral tilt angles are 34°. There are a spread of S–O bond distances ranging from 1.47–1.52 Å. In the second S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share a cornercorner with one FeO6 octahedra. The corner-sharing octahedral tilt angles are 32°. There are a spread of S–O bond distances ranging from 1.48–1.51 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe+2.67+ and one S6+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one H1+ and one S6+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one S6+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one S6+ atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Fe+2.67+ and one S6+ atom. In the sixth O2- site, O2- is bonded in a single-bond geometry to one S6+ atom. In the seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two H1+ and one S6+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one H1+ and one S6+ atom. In the ninth O2- site, O2- is bonded in a distorted water-like geometry to one Fe+2.67+ and two H1+ atoms. In the tenth O2- site, O2- is bonded in a distorted water-like geometry to one Fe+2.67+ and two H1+ atoms. In the eleventh O2- site, O2- is bonded in a distorted water-like geometry to one Fe+2.67+ and two H1+ atoms. In the twelfth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Fe+2.67+ and two H1+ atoms.
Large-scale stationary storage forms a key sector that can be economically served by sodium-ion batteries. In realizing practical sodium-ion batteries, discovery and development of novel cathodes is essential. In this spirit, alluaudite-type Na 2 Fe 2 (SO 4 ) 3 was reported in 2014 to have the highest Fe 3+ /Fe 2+ redox potential (~3.8 V vs. Na). This finding led to reports on various PO4 3– and SO4 2– based alluaudite compounds exhibiting high energy densities. In 2017, MoO 4 2– based alluaudite, Na 2.67 Mn 1.67 (MoO 4 ) 3 , was found as a 3.45 V cathode material. Exploring molybdenum chemistry further, this work reports alluaudite type Na 3.36 Co 1.32 (MoO 4 ) 3 (NCMo) as a novel versatile electroactive cathode for Li-ion and Na-ion batteries. It was synthesized by a wet solution-combustion route with a restricted annealing duration of 1 min at 600 °C. Calorimetric study revealed the formation enthalpy from component oxides (ΔH° f,ox = –575.49 ± 7.75 kJ/mol) to be highly exothermic. Unlike the sulfate class of alluaudites, this material is highly stable in air and moisture (ΔH ds = 537.42 ± 0.78 kJ/mol). Having an ionic conductivity of 6.065 × 10 –8 S/cm (at 50 °C), it offers a pseudo two-dimensional Na + migration pathway. Without any material optimization, NCMo was found to work as a high-voltage insertion cathode (ca. 4.0 V vs. Na/Na + and 4.1 V vs. Li/Li + ) in sync with theoretically predicted potential of 3.98 V (vs. Na/Na + ). Ex-situ X-ray diffraction and photoelectron spectroscopy studies revealed the occurrence of solid-solution redox mechanism solely involving Co 3+ /Co 2+ redox centre. Finally, it benchmarks Na 3.36 Co 1.32 (MoO 4 ) 3 as a novel electrochemically active Mo-based alluaudite-type polyanionic cathode insertion material.
Green rusts (GR) are mixed-valence iron (Fe) hydroxides which form in reducing redox environments like riparian and wetland soils and shallow groundwater. In these environments, silicon (Si) can influence Fe oxides’ chemical and physical properties but its role in GR formation and subsequent oxidative transformation have not been studied starting at initial nucleation. Green rust sulfate [GR(SO 4 )] and green rust carbonate [GR(CO 3 )] were both coprecipitated from salts by base titration in increasing % mol Si (0, 1, 10, and 50). The minerals were characterized before and after rapid (24 h) aqueous air-oxidation by x-ray diffraction (XRD), scanning electron microscopy (SEM), Fe extended x-ray absorption fine structure spectroscopy (EXAFS), and N 2 -BET surface area. Results showed that only GR(SO4) or GR(CO3) was formed at every tested Si concentration. Increasing % mol Si caused decreased plate size and increased surface area in GR(CO3) but not GR(SO4). GR plate basal thickness was not changed at any condition indicating a lack of Si interlayering. Air oxidation of GR(SO4) at all % mol Si contents transformed by dissolution and reprecipitation into lepidocrocite and goethite, favoring ferrihydrite with higher % Si content. Air oxidation of GR(CO3) transformed into magnetite and goethite but increasing Si caused GR to oxidize while retaining its hexagonal plate structure via solid-state oxidation. Our results indicate that Si has the potential to cause GR to form in smaller particles and upon air oxidation, Si can either stabilize the plate structure or alter transformation to ferrihydrite.
FeH4(SO5)2 crystallizes in the triclinic P-1 space group. The structure is one-dimensional and consists of one FeH4(SO5)2 ribbon oriented in the (0, 0, 1) direction. Fe is bonded to six O atoms to form FeO6 octahedra that share corners with four SO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.00–2.07 Å. There are four inequivalent H sites. In the first H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.99 Å. In the second H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.99 Å. In the third H site, H is bonded in a single-bond geometry to two O atoms. There is one shorter (1.00 Å) and one longer (1.70 Å) H–O bond length. In the fourth H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.99 Å. There are two inequivalent S sites. In the first S site, S is bonded to four O atoms to form SO4 tetrahedra that share corners with two equivalent FeO6 octahedra. The corner-sharing octahedral tilt angles are 43°. There are a spread of S–O bond distances ranging from 1.46–1.52 Å. In the second S site, S is bonded to four O atoms to form SO4 tetrahedra that share corners with two equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 41–47°. There are a spread of S–O bond distances ranging from 1.46–1.51 Å. There are ten inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one S atom. In the second O site, O is bonded in a distorted trigonal planar geometry to one Fe and two H atoms. In the third O site, O is bonded in a distorted water-like geometry to one H and one S atom. In the fourth O site, O is bonded in a distorted single-bond geometry to one S atom. In the fifth O site, O is bonded in a single-bond geometry to one S atom. In the sixth O site, O is bonded in a distorted bent 150 degrees geometry to one Fe and one S atom. In the seventh O site, O is bonded in a distorted bent 150 degrees geometry to one Fe and one S atom. In the eighth O site, O is bonded in a bent 150 degrees geometry to one Fe and one S atom. In the ninth O site, O is bonded in a distorted bent 120 degrees geometry to one Fe and one S atom. In the tenth O site, O is bonded in a distorted trigonal non-coplanar geometry to one Fe and two H atoms.