03 Fakultät Chemie
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Item Open Access Confirmation of siderazot, Fe3N1.33, the only terrestrial nitride mineral(2021) Bette, Sebastian; Theye, Thomas; Bernhardt, Heinz-Jürgen; Clark, William P.; Niewa, RainerSiderazot, the only terrestrial nitride mineral, was reported only once in 1876 to occur as coating on volcanic rocks in a fumarolic environment from Mt. Etna and, to date, has been neither confirmed nor structurally characterized. We have studied the holotype sample from the Natural History Museum, London, UK, originally collected by O. Silvestri in 1874, and present siderazot with epsilon-Fe3N-type crystal structure and composition of Fe3N1.33(7) according to crystal structure Rietveld refinements, in good agreement with electron microprobe analyses. Crystal structure data, chemical composition, and Raman and reflectance measurements are reported. Possible formation conditions are derived from composition and phase stability data according to synthetic samples.Item Open Access On the thermal dimorphy of the strontium perrhenate Sr[ReO4]2(2024) Conrad, Maurice; Bette, Sebastian; Dinnebier, Robert E.; Schleid, ThomasHygroscopic single crystals of a new hexagonal high‐temperature modification of Sr[ReO4]2 were prepared from a melt of Sr[ReO4]2 ⋅ H2O and SrCl2 ⋅ 6 H2O. The structure analysis of the obtained crystals by X‐ray diffraction revealed that the title compound crystallizes in the ThCd[MoO4]3‐type structure with the hexagonal space group P63/m and the lattice parameters a=1023.81(7) pm and c=646.92(4) pm (c/a=0.632) for Z=2 in its quenchable high‐temperature form. Two crystallographically independent Sr2+ cations are coordinated by oxygen atoms forming either octahedra or tricapped trigonal prisms, whereas the Re7+ cations are found in the centers of discrete tetrahedral meta‐perrhenate units [ReO4]-. Temperature‐dependent in‐situ PXRD studies of dry powder samples of Sr[ReO4]2 exhibited its thermal dimorphy with a phase‐transition temperature at 500-550 °C from literature‐known m‐Sr[ReO4]2 into the newly discovered h‐Sr[ReO4]2 (hexagonal).Item Open Access Monomeric and dimeric (aminomethylidene)phosphines and -arsines(1986) Becker, Gerd; Mayer, M.; Mundt, Otto; Riffel, Heinz; Wessely, Hans-Jürgen; Simon, Arndt-Item Open Access Sulfurized polypropylene as low‐cost cathode material for high‐capacity lithium‐sulfur batteries(2022) Du, Qian; Benedikter, Mathis; Küster, Kathrin; Acartürk, Tolga; Starke, Ulrich; Hoslauer, Jean‐Louis; Schleid, Thomas; Buchmeiser, Michael R.Among ‘beyond lithium ion’ energy storage, lithium sulfur (Li-S) batteries are one of the most promising technologies, as a result of the potential for high theoretical energy capacity at low cost. A key obstacle in exploiting the vast potential of Li-S batteries is the formation of soluble polysulfide species. Here, we report sulfurized polypropylene (S/PP‐500) synthesized in one‐step by reacting polypropylene (PP) with sulfur as a new polysulfide shuttle‐free cathode material for Li-S batteries. It exhibits a reversible capacity as high as 1000 mAh/gsulfur at 0.1 C and a sulfur loading of up to 68 wt%, which in turn allows for high sulfur loadings up to 47 % in the final cathode. The low‐cost starting materials together with the simple synthetic procedure and the good electrochemical performance in combination with a commercially available eslectrolyte make the S/PP‐500 a very promising cathode material for Li‐S batteries.Item Open Access Intermolekulare Sb···Sb-Wechselwirkungen im kristallinen Tetramethyldistiban (Element-Element-Bindungen ; 3)(1984) Mundt, Otto; Riffel, Heinz; Becker, Gerd; Simon, ArndtTetramethyldistibane which shows a colour change from deep red to pale yellow upon melting, has been subjected to single-crystal x-ray diffraction analyses at -21° and -139°C (orthorhombic, Pnma, Z = 4, -139°C: a = 1150.9(3); b = 1136.8(2); c = 651.6(2) pm). The molecules adopt the antiperiplanar conformation with the crystallographically imposed symmetry m (c 3) and are aligned in extended linear antimony chains with short intermolecular contacts (-139 °C: Sb-Sb 283.8(1), Sb···Sb 367.8(1) pm; Sb-Sb...Sb 179.2°). The structure is compared with those of similar compounds.Item Open Access Molekül- und Kristallstruktur des Tetramethyldiphosphans und -diarsans (Element-Element-Bindungen ; 4)(1988) Mundt, Otto; Riffel, Heinz; Becker, Gerd; Simon, ArndtThe molecular and crystal structures of the isotypic compounds tetramethyldiphosphane 1 and -diarsane 2 have been determined by single crystal X-ray diffraction (monoclinic; C2/m; Z = 2; 1/2: -155/-144 ·C°; a = 540.6(2)/555.8(2); b = 1131.0(6)/1136.7(6); c = 602.5(2)/612.8(2) pm;β = 97.31(3)/95.24(3)"; P-P 221.2(1)/As-As242.9(1) pm). In accordance with the crystallographically imposed symmetry 2/m, the molecules adopt antiperiplanar conformation. Their crystal structures are c10sely related to those of the homologues tetramethyldistibane 3 [1] and -dibismuthane 4 [3]. As found for the latter compounds, the E-E units (E = P, As) are also aligned in linear chains, but the intermolecular E···E contacts (P...P 381/As...As 370 pm) do not allow any extended interaction between molecules, which otherwise would result in thermochromic effects.Item Open Access Li4Ln[PS4]2Cl : chloride-containing lithium thiophosphates with lanthanoid participation (Ln = Pr, Nd and Sm)(2023) Lange, Pia L.; Bette, Sebastian; Strobel, Sabine; Dinnebier, Robert E.; Schleid, ThomasThe synthesis and structural analysis of three new chloride-containing lithium thiophosphates(V) Li4Ln[PS4]2Cl with trivalent lanthanoids (Ln = Pr, Nd and Sm) are presented and discussed. Single crystals of Li4Sm[PS4]2Cl were obtained and used for crystal structure determination by applying X-ray diffraction. The other compounds were found to crystallize isotypically in the monoclinic space group C2/c. Thus, Li4Sm[PS4]2Cl (a = 2089.31(12) pm, b = 1579.69(9) pm, c = 1309.04(8) pm, β = 109.978(3)°, Z = 12) was used as a representative model to further describe the crystal structure in detail since Li4Pr[PS4]2Cl and Li4Nd[PS4]2Cl were confirmed to be isotypic using powder X-ray diffraction measurements (PXRD). In all cases, a trigonal structure in the space group R3̲ (e.g., a = 1579.67(9) pm, c = 2818.36(16) pm, c/a = 1.784, Z = 18, for Li4Sm[PS4]2Cl) displaying almost identical building units worked initially misleadingly. The structure refinement of Li4Sm[PS4]2Cl revealed bicapped trigonal prisms of sulfur atoms coordinating the two crystallographically distinct (Sm1)3+ and (Sm2)3+ cations, which are further coordinated by four anionic [PS4]3- tetrahedra. The compounds also contain chloride anions residing within channel-like pores made of [PS4]3- units. Eight different sites for Li+ cations were identified with various coordination environments (C.N. = 4-6) with respect to chlorine and sulfur. EDXS measurements supported the stoichiometric formula of Li4Ln[PS4]2Cl, and diffuse reflectance spectroscopy revealed optical band gaps of 2.69 eV, 3.52 eV, and 3.49 eV for Li4Sm[PS4]2Cl, Li4Nd[PS4]2Cl, and Li4Pr[PS4]2Cl, respectively. The activation energy for Li+-cation mobility in Li4Sm[PS4]2Cl was calculated as Ea(Li+) = 0.88 eV using BVEL, which indicates potential as a Li+-cation conductor.Item Open Access Crystal structure of trichloro(3,3’)-trimethylene- 2,2’-biquinoline)gold(III) chloroform hemisolvate, [(C9H5N)(CH3)][(C9H6N)(CH3)]AuCl3 · 0.5 CHCl3 and of tribromo(3,3’)-trimethylene-2,2’-biquinoline)gold(III) chloroform hemisolvate, [(C9H5N)(CH3)] [(C9H6N)(CH3)]AuBr3 · 0.5CHCl3(2014) Peters, K.; Peters, E.-M.; Schnering, H. G. von; Hönle, W.; Schmidt, R.; Binder, HerbertC21.5H16.5AuCl4.5N2, monoclinic, P12i/nl (No. 14), a = 9.777(2) Å, b = 18.734(4) Å, c = 12.339(2) Å, β = 101.87(3)°, V= 2211.7 Å3, Z = 4, Rgt(F) = 0.034, wR(F) = 0.031, T = 293 Κ.Item Open Access Crystal structure of pyridinogold(III) bromide, [AuBr2(C5H5N)2]+[AuBr4[AuBr3(C5H5N)]2, a frozen-in autoionization system(2014) Peters, K.; Peters, E.-M.; Schnering, H. G. von; Hönle, W.; Schmidt, R.; Binder, HerbertC10H10Au2Br6N2, monoclinic, Pl2/nl (No. 14), a = 11.395(2) A, b = 15.437(2) Å, c = 11.091(2) Å, β = 99.44(1)°, V= 1924.5 Å3 ,Z = 4, Rgt(F) = 0.063, wR(F) = 0.050, Τ = 293 Κ.Item Open Access Crystal structure of bis(3,3’-trimethylene-2,2’-biquinolinium)(1+) dibromoaurate(I)(1-) tetrabromoaurate(III)(1-), (C21H16N2H)2[AuBr2][AuBr4], a mixed valence Au(I)/Au(III) salt(2014) Hönle, W.; Peters, Κ.; Peters, E.-M.; Schnering, H. G. von; Schmidt, R.; Moya, S. A.; Gullpi, M.; Binder, HerbertC21H17AuBr3N2, triclinic, P-1 (No. 2), a = 10.296(2) Å, b = 12.875(3) Å,c = 8.901(2) Å, α = 105.84(2)°, β = 109.52(1)°, γ = 74.66(2)°, V = 1050.1 Κ , Ζ = 2, Rgt(F) = 0.046, wR(F) = 0.042, Τ = 293 Κ.