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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
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
VTl(SO4)2 crystallizes in the trigonal P321 space group. The structure is three-dimensional. V5+ is bonded to six equivalent O2- atoms to form distorted VO6 octahedra that share corners with six equivalent SO4 tetrahedra and faces with two equivalent TlO12 cuboctahedra. All V–O bond lengths are 2.05 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 VO6 octahedra. There are six shorter (3.08 Å) and six longer (3.44 Å) Tl–O bond lengths. S5+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three equivalent VO6 octahedra and edges with three equivalent TlO12 cuboctahedra. The corner-sharing octahedral tilt angles are 32°. 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 V5+, one Tl1+, and one S5+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to three equivalent Tl1+ and one S5+ atom.
LiV(SO4)2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight 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 1.92–2.51 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 1.95–2.54 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 1.94–2.70 Å. In the fourth 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 1.94–2.41 Å. In the fifth 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 1.97–2.56 Å. In the sixth 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 1.96–2.55 Å. In the seventh Li1+ site, Li1+ is bonded to six O2- atoms to form distorted LiO6 pentagonal pyramids that share corners with four VO6 octahedra, corners with two SO4 tetrahedra, and edges with two SO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–58°. There are a spread of Li–O bond distances ranging from 1.96–2.28 Å. In the eighth Li1+ site, Li1+ is bonded to six O2- atoms to form distorted LiO6 pentagonal pyramids that share corners with four VO6 octahedra, corners with two SO4 tetrahedra, and edges with two SO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–57°. There are a spread of Li–O bond distances ranging from 1.99–2.26 Å. There are eight inequivalent V5+ sites. In the first V5+ site, V5+ is bonded to six O2- atoms to form VO6 octahedra that share a cornercorner with one LiO6 pentagonal pyramid and corners with six SO4 tetrahedra. There are a spread of V–O bond distances ranging from 2.02–2.12 Å. In the second V5+ site, V5+ is bonded to six O2- atoms to form VO6 octahedra that share a cornercorner with one LiO6 pentagonal pyramid and corners with six SO4 tetrahedra. There are a spread of V–O bond distances ranging from 2.00–2.15 Å. In the third V5+ site, V5+ is bonded to six O2- atoms to form VO6 octahedra that share a cornercorner with one LiO6 pentagonal pyramid and corners with six SO4 tetrahedra. There are a spread of V–O bond distances ranging from 1.98–2.10 Å. In the fourth V5+ site, V5+ is bonded to six O2- atoms to form VO6 octahedra that share a cornercorner with one LiO6 pentagonal pyramid and corners with six SO4 tetrahedra. There are a spread of V–O bond distances ranging from 2.01–2.11 Å. In the fifth V5+ site, V5+ is bonded to six O2- atoms to form VO6 octahedra that share corners with six SO4 tetrahedra. There are a spread of V–O bond distances ranging from 2.04–2.08 Å. In the sixth V5+ site, V5+ is bonded to six O2- atoms to form VO6 octahedra that share corners with six SO4 tetrahedra. There are a spread of V–O bond distances ranging from 2.01–2.11 Å. In the seventh V5+ site, V5+ is bonded to six O2- atoms to form VO6 octahedra that share corners with two LiO6 pentagonal pyramids and corners with six SO4 tetrahedra. There are a spread of V–O bond distances ranging from 1.99–2.11 Å. In the eighth V5+ site, V5+ is bonded to six O2- atoms to form VO6 octahedra that share corners with two LiO6 pentagonal pyramids and corners with six SO4 tetrahedra. There are a spread of V–O bond distances ranging from 2.02–2.11 Å. There are sixteen inequivalent S5+ sites. In the first S5+ site, S5+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three VO6 octahedra and a cornercorner with one LiO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 34–48°. There are a spread of S–O bond distances ranging from 1.47–1.51 Å. In the second S5+ site, S5+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three VO6 octahedra and a cornercorner with one LiO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 37–47°. There are a spread of S–O bond distances ranging from 1.47–1.51 Å. In the third S5+ site, S5+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three VO6 octahedra and an edgeedge with one LiO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 48–51°. There are a spread of S–O bond distances ranging from 1.45–1.51 Å. In the fourth S5+ site, S5+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three VO6 octahedra and an edgeedge 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 1.44–1.52 Å. In the fifth S5+ site, S5+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three VO6 octahedra. The corner-sharing octahedra tilt angles range from 46–50°. There are a spread of S–O bond distances ranging from 1.46–1.53 Å. In the sixth S5+ site, S5+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three VO6 octahedra. The corner-sharing octahedra tilt angles range from 44–45°. There are a spread of S–O bond distances ranging from 1.45–1.51 Å. In the seventh S5+ site, S5+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three VO6 octahedra. The corner-sharing octahedra tilt angles range from 40–48°. There are a spread of S–O bond distances ranging from 1.43–1.55 Å. In the eighth S5+ site, S5+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three VO6 octahedra. The corner-sharing octahedra tilt angles range from 39–49°. There are a spread of S–O bond distances ranging from 1.43–1.55 Å. In the ninth S5+ site, S5+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three VO6 octahedra. The corner-sharing octahedra tilt angles range from 40–49°. There are a spread of S–O bond distances ranging from 1.44–1.52 Å. In the tenth S5+ site, S5+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three VO6 octahedra. The corner-sharing octahedra tilt angles range from 37–49°. There are a spread of S–O bond distances ranging from 1.44–1.53 Å. In the eleventh S5+ site, S5+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three VO6 octahedra and a cornercorner 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 1.45–1.51 Å. In the twelfth S5+ site, S5+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three VO6 octahedra and a cornercorner with one LiO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 44–47°. There are a spread of S–O bond distances ranging from 1.46–1.52 Å. In the thirteenth S5+ site, S5+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three VO6 octahedra. The corner-sharing octahedra tilt angles range from 47–50°. There are a spread of S–O bond distances ranging from 1.45–1.51 Å. In the fourteenth S5+ site, S5+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three VO6 octahedra. The corner-sharing octahedral tilt angles are 46°. There are a spread of S–O bond distances ranging from 1.45–1.51 Å. In the fifteenth S5+ site, S5+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three VO6 octahedra and an edgeedge with one LiO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 38–48°. There are a spread of S–O bond distances ranging from 1.45–1.53 Å. In the sixteenth S5+ site, S5+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three VO6 octahedra and an edgeedge with one LiO6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 37–48°. There are a spread of S–O bond distances ranging from 1.45–1.53 Å. There are sixty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one V5+, and one S5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one V5+, and one S5+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Li1+ and one S5+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one Li1+ and one S5+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one V5+, and one S5+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one V5+, and one S5+ atom. In the seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one V5+, and one S5+ atom. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to one V5+ and one S5+ atom. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one V5+, and one S5+ atom. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one V5+, and one S5+ atom. In the eleventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one V5+ and one S5+ atom. In the twelfth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one V5+, and one S5+ atom. In the thirteenth O2- site, O2- is bonded in a bent 150 degrees geometry to one V5+ and one S5+ atom. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one V5+, and one S5+ atom. In the fifteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Li1+ and one S5+ atom. In the sixteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Li1+ and one S5+ atom. In the seventeenth O2- site, O2- is bonded in a 2-coordinate geometry to two Li1+ and one S5+ atom. In the eighteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Li1+ and one S5+ atom. In the nineteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one V5+, and one S5+ atom. In the twentieth O2- site, O2- is bonded in a bent 150 degrees geometry to one V5+ and one S5+ atom. In the twenty-first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one V5+, and one S5+ atom. In the twenty-second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V5+ and one S5+ atom. In the twenty-third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V5+ and one S5+ atom. In the twenty-fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one V5+ and one S5+ atom. In the twenty-fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one V5+ and one S5+ atom. In the twenty-sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one V5+, and one S5+ atom. In the twenty-seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one V5+, and one S5+ atom. In the twenty-eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one V5+, and one S5+ atom. In the twenty-ninth O2- site, O2- is bonded in a bent 120 degrees geometry to one Li1+ and one S5+ atom. In the thirtieth O2- site, O2- is bonded in a bent 120 degrees geometry to one Li1+ and one S5+ atom. In the thirty-first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one V5+ and one S5+ atom. In the thirty-second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V5+ and one S5+ atom. In the thirty-third O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one V5+, and one S5+ atom. In the thirty-fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V5+ and one S5+ atom. In the thirty-fifth O2- site, O2- is bonded in a single-bond geometry to one S5+ atom. In the thirty-sixth O2- site, O2- is bonded in a single-bond geometry to one S5+ atom. In
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.
Abstract Seaborgite (IMA2019-087), LiNa6K2(UO2)(SO4)5(SO3OH)(H2O), is a new mineral species from the Blue Lizard mine, Red Canyon, San Juan County, Utah, U.S.A. It is a secondary phase found on gypsum in association with copiapite, ferrinatrite, ivsite, metavoltine, and römerite. Seaborgite occurs in sprays of light-yellow, long flattened prisms or blades, up to about 0.2 mm in length. Crystals are elongated on [100], flattened on {010}, and exhibit the forms {100}, {010}, {001}, and {101}. The mineral is transparent with vitreous luster and very pale-yellow streak. It exhibits bright lime-green fluorescence under a 405 nm laser. The Mohs hardness is ~2½. The mineral has brittle tenacity, curved or conchoidal fracture, and one good cleavage on {100}. The measured density is 2.97(2) g/cm3. The mineral is immediately soluble in H2O at room temperature. The mineral is optically biaxial (–), α = 1.505(2), β = 1.522(2), γ = 1.536(2) (white light); 2Vmeas = 85(1)°; moderate r < ν dispersion; orientation X ^ a ≈ 10°; pleochroic X colorless, Y and Z light green-yellow; X < Y ≈ Z. EPMA and LA-ICP-MS analyses of seaborgite undermeasured its Li, K, and Na. The empirical formula using Li, Na, and K based on the structure refinement is Li1.00Na5.81K2.19(UO2)(SO4)5(SO3OH)(H2O). Seaborgite is triclinic, P1, a = 5.4511(4), b = 14.4870(12), c = 15.8735(15) Å, α = 76.295(5), β = 81.439(6), γ = 85.511(6)°, V = 1203.07(18) Å3, and Z = 2. The structure (R1 = 0.0377 for 1935 I = 2σI) contains [(UO2)2(SO4)8]4– uranyl-sulfate clusters that are linked into a band by bridging LiO4 tetrahedra. The bands are linked through peripheral SO4 tetrahedra forming a thick heteropolyhedral layer. Channels within the layers contain a K site, while an additional K site, six Na sites, and an SO3OH group occupy the space between the heteropolyhedral layers.
Pyrite oxidation plays a critical role in the relationship between weathering and climate, and its impact on the global carbon cycle has previously been constrained through inversion models utilizing observations of river sulfate ($SO^{2–}_{4}$) and its 34 S/ 32 S isotope ratio (δ 34 S SO4 ). However, measurements from some rivers have suggested that SSO4 can be substantially impacted by processes such as microbial sulfate reduction and/or sulfur assimilation and cycling, rather than simply reflecting a weighted mixture of lithologic sulfur sources. To study the prevalence and controls on $SO^{2–}_{4}$ transformations, in this study we measured dissolved major element concentrations and δ 34 S SO4 in river water samples from throughout western Iceland. Our analyses focused on samples from a small catchment hosting the Efri Haukadalsá river, a system with relatively uniform and isotopically constrained basaltic bedrock. We also measured sediment δ 34 S and sulfur speciation using sulfur K-edge X-ray absorption spectroscopy on sediment and vegetation samples from this catchment. Values of dissolved δ 34 S SO4 in the Efri Haukadalsá ranged from 2.5‰ to 23.7‰ and had a linear relationship with Cl – /$SO^{2–}_{4}$ ratios, indicating that $SO^{2–}_{4}$ predominantly derived from basalt weathering and meteoric precipitation. The lower δ 34 S SO4 values were found in fluvial valleys with V-shaped cross sections, while higher values of δ 34 S SO4 occurred in U-shaped, glacially eroded valleys with thick alluvial fills blanketing the valley floor. Spectroscopic observations identified organic sulfur phases in suspended river sediment, floodplain deposits, and vegetation. Mass balance calculations quantified the organic sulfur flux as less than 10% of $SO^{2–}_{4}$ export, and sediment δ 34 S values were comparable to river δ 34 S SO4 . We interpreted these isotopic and chemical patterns as reflecting differences in the availability of unweathered bedrock across the Efri Haukadalsá catchment, with V-shaped valleys having greater access to fresh sulfide-bearing minerals than alluviated U-shaped valleys; this interpretation is in contrast to one in which the elevated δ 34 S SO4 values reflect fractionation during sulfur transformations along alluvial reaches. These results validated the application of river inversion models for constraining weathering fluxes and affirmed that pyrite oxidation globally, even in the presence of river sulfur cycling, modulates the abundance of atmospheric carbon dioxide.
Li3V(SO4)3 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Li1+ is bonded in a 1-coordinate geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.94–2.42 Å. There are two inequivalent V5+ sites. In the first V5+ site, V5+ is bonded to six equivalent O2- atoms to form VO6 octahedra that share corners with six equivalent SO4 tetrahedra. All V–O bond lengths are 2.05 Å. In the second V5+ site, V5+ is bonded to six equivalent O2- atoms to form VO6 octahedra that share corners with six equivalent SO4 tetrahedra. All V–O bond lengths are 2.00 Å. S+5.33+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with two VO6 octahedra. The corner-sharing octahedra tilt angles range from 38–47°. There are a spread of S–O bond distances ranging from 1.46–1.51 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one V5+ and one S+5.33+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Li1+ and one S+5.33+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Li1+ and one S+5.33+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one V5+ and one S+5.33+ atom.
VTl2(SO5)2 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. V4+ is bonded to six O2- atoms to form distorted VO6 octahedra that share corners with four SO4 tetrahedra. There are a spread of V–O bond distances ranging from 1.67–2.09 Å. There are two inequivalent Tl2+ sites. In the first Tl2+ site, Tl2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Tl–O bond distances ranging from 2.89–3.21 Å. In the second Tl2+ site, Tl2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Tl–O bond distances ranging from 2.87–3.16 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 corners with two equivalent VO6 octahedra. The corner-sharing octahedra tilt angles range from 41–42°. There are a spread of S–O bond distances ranging from 1.45–1.57 Å. In the second S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with two equivalent VO6 octahedra. The corner-sharing octahedra tilt angles range from 36–46°. There are a spread of S–O bond distances ranging from 1.46–1.54 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Tl2+ and one S6+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one V4+ and one Tl2+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one V4+ and one Tl2+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to one Tl2+ and one S6+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V4+, one Tl2+, and one S6+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one V4+, one Tl2+, and one S6+ atom. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to two Tl2+ and one S6+ atom. In the eighth O2- site, O2- is bonded in a single-bond geometry to two Tl2+ and one S6+ atom. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to one V4+, one Tl2+, and one S6+ atom. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to one V4+, one Tl2+, and one S6+ atom.
NaV3(SO7)2 crystallizes in the trigonal R32 space group. The structure is three-dimensional. Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with six equivalent SO4 tetrahedra and faces with six equivalent VO6 octahedra. There are six shorter (2.86 Å) and six longer (2.96 Å) Na–O bond lengths. V5+ is bonded to six O2- atoms to form distorted VO6 octahedra that share corners with four equivalent VO6 octahedra, corners with two equivalent SO4 tetrahedra, and faces with two equivalent NaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 39°. There are a spread of V–O bond distances ranging from 1.70–2.09 Å. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three equivalent NaO12 cuboctahedra and corners with three equivalent VO6 octahedra. The corner-sharing octahedral tilt angles are 51°. There is one shorter (1.43 Å) and three longer (1.52 Å) S–O bond length. There are three 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 2-coordinate geometry to one Na1+, one V5+, and one S6+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+ and two equivalent V5+ atoms.
Li3V2S2(O4F3)2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a distorted L-shaped geometry to one O2- and one F1- atom. The Li–O bond length is 1.93 Å. The Li–F bond length is 1.91 Å. In the second Li1+ site, Li1+ is bonded in a 2-coordinate geometry to two O2- and two F1- atoms. There are one shorter (1.95 Å) and one longer (2.65 Å) Li–O bond lengths. There are one shorter (1.92 Å) and one longer (2.67 Å) Li–F bond lengths. In the third Li1+ site, Li1+ is bonded in a 3-coordinate geometry to three O2- and two F1- atoms. There are a spread of Li–O bond distances ranging from 1.96–2.63 Å. There is one shorter (1.94 Å) and one longer (2.03 Å) Li–F bond length. In the fourth Li1+ site, Li1+ is bonded in a distorted see-saw-like geometry to two O2- and two F1- atoms. There are one shorter (1.98 Å) and one longer (2.29 Å) Li–O bond lengths. There are one shorter (2.08 Å) and one longer (2.10 Å) Li–F bond lengths. In the fifth Li1+ site, Li1+ is bonded in a 4-coordinate geometry to two O2- and two F1- atoms. There are one shorter (2.00 Å) and one longer (2.32 Å) Li–O bond lengths. There are one shorter (2.05 Å) and one longer (2.16 Å) Li–F bond lengths. In the sixth Li1+ site, Li1+ is bonded in a distorted trigonal non-coplanar geometry to one O2- and two F1- atoms. The Li–O bond length is 1.94 Å. There is one shorter (1.90 Å) and one longer (2.02 Å) Li–F bond length. There are four inequivalent V+3.50+ sites. In the first V+3.50+ site, V+3.50+ is bonded to two O2- and four F1- atoms to form VO2F4 octahedra that share corners with two equivalent VO2F4 octahedra and corners with two SO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–53°. There are one shorter (1.97 Å) and one longer (2.05 Å) V–O bond lengths. There are a spread of V–F bond distances ranging from 1.89–2.04 Å. In the second V+3.50+ site, V+3.50+ is bonded to two O2- and four F1- atoms to form VO2F4 octahedra that share corners with two equivalent VO2F4 octahedra and corners with two SO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–51°. There is one shorter (1.94 Å) and one longer (1.99 Å) V–O bond length. There are a spread of V–F bond distances ranging from 1.83–1.94 Å. In the third V+3.50+ site, V+3.50+ is bonded to two O2- and four F1- atoms to form VO2F4 octahedra that share corners with two equivalent VO2F4 octahedra and corners with two SO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–53°. There is one shorter (1.94 Å) and one longer (1.99 Å) V–O bond length. There are a spread of V–F bond distances ranging from 1.83–1.95 Å. In the fourth V+3.50+ site, V+3.50+ is bonded to two O2- and four F1- atoms to form VO2F4 octahedra that share corners with two equivalent VO2F4 octahedra and corners with two SO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–51°. There are one shorter (1.97 Å) and one longer (2.05 Å) V–O bond lengths. There are a spread of V–F bond distances ranging from 1.89–2.03 Å. There are four inequivalent S6+ sites. In the first S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with two VO2F4 octahedra. The corner-sharing octahedra tilt angles range from 45–54°. There are a spread of S–O bond distances ranging from 1.45–1.56 Å. In the second S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with two VO2F4 octahedra. The corner-sharing octahedra tilt angles range from 46–53°. There are a spread of S–O bond distances ranging from 1.45–1.57 Å. In the third S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with two VO2F4 octahedra. The corner-sharing octahedra tilt angles range from 50–54°. There are a spread of S–O bond distances ranging from 1.46–1.55 Å. In the fourth S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with two VO2F4 octahedra. The corner-sharing octahedra tilt angles range from 49–54°. There are a spread of S–O bond distances ranging from 1.46–1.54 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one V+3.50+ and one S6+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one V+3.50+ and one S6+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Li1+ and 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 distorted single-bond geometry to one Li1+ and one S6+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to one Li1+ and one S6+ atom. In the seventh O2- site, O2- is bonded in a bent 120 degrees geometry to one V+3.50+ and one S6+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+, one V+3.50+, and one S6+ atom. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+, one V+3.50+, and one S6+ atom. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one V+3.50+, and one S6+ atom. In the eleventh O2- site, O2- is bonded in a bent 120 degrees geometry to one Li1+ and one S6+ atom. In the twelfth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Li1+ and one S6+ atom. In the thirteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Li1+ and one S6+ atom. In the fourteenth O2- site, O2- is bonded in a bent 120 degrees geometry to one Li1+ and one S6+ atom. In the fifteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one V+3.50+, and one S6+ atom. In the sixteenth O2- site, O2- is bonded in a 2-coordinate geometry to one V+3.50+ and one S6+ atom. There are twelve inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted bent 120 degrees geometry to one Li1+ and one V+3.50+ atom. In the second F1- site, F1- is bonded in a distorted trigonal planar geometry to two Li1+ and one V+3.50+ atom. In the third F1- site, F1- is bonded in a distorted bent 120 degrees geometry to two V+3.50+ atoms. In the fourth F1- site, F1- is bonded in a distorted bent 120 degrees geometry to two V+3.50+ atoms. In the fifth F1- site, F1- is bonded in a distorted trigonal planar geometry to two Li1+ and one V+3.50+ atom. In the sixth F1- site, F1- is bonded in a bent 120 degrees geometry to one Li1+ and one V+3.50+ atom. In the seventh F1- site, F1- is bonded in a distorted bent 120 degrees geometry to two Li1+ and one V+3.50+ atom. In the eighth F1- site, F1- is bonded in a bent 120 degrees geometry to one Li1+ and one V+3.50+ atom. In the ninth F1- site, F1- is bonded in a bent 120 degrees geometry to two V+3.50+ atoms. In the tenth F1- site, F1- is bonded in a distorted bent 120 degrees geometry to two V+3.50+ atoms. In the eleventh F1- site, F1- is bonded in a distorted bent 120 degrees geometry to one Li1+ and one V+3.50+ atom. In the twelfth F1- site, F1- is bonded in a bent 120 degrees geometry to one Li1+ and one V+3.50+ atom.
A Li-rich polyanionic compound based on V 3+ with a previously unknown structure, Li 5 VF 4 (SO 4 ) 2 , has been developed as a high-voltage cathode material for Li-ion batteries. The solvothermal preparation of this material, crystal structure solution, and initial electrochemical characterization are presented. An analysis based on density functional theory electronic structure calculations suggests that a high voltage close to 5 V is required to extract two Li ions and to reach the oxidation state of V 5+ . However, the use of conventional carbonate-based electrolytes, which exhibit increasing degradation above a potential of 4.3 V, does not permit the full capacity of this compound to be achieved at this time.