Synthese und Kristallstruktur von Hydrogensulfaten einwertiger Metalle – Ag(H3O)(HSO4)2, Ag2(HSO4)2(H2SO4), AgHSO4 und Hg2(HSO4)2

Synthesis and Crystal Structure of Metal(I) Hydrogen Sulfates – Ag(H₃O)(HSO₄)₂, Ag₂(HSO₄)₂(H₂SO₄), AgHSO₄, and Hg₂(HSO₄)₂ Hydrogen sulfates Ag(H₃O)(HSO₄)₂, Ag₂(HSO₄)₂ · (H₂SO₄), and AgHSO₄ have been synthesized from Ag₂SO₄ and sulfuric acid. Hg₂(HSO₄)₂ was obtained from metallic mercury and 96% sulfuric acid as starting materials. The compounds were characterized by X‐ray single crystal structure determination. Ag(H₃O)(HSO₄)₂ belongs to the structure type of Na(H₃O)(HSO₄). The silver atom is coordinated by 6 + 2 oxygen atoms. In the structure, there are dimers and chains of hydrogen bonded HSO₄^– tetrahedra. Dimers and chains are connected by the H₃O⁺ ion to form a three dimensional hydrogen network. Ag₂(HSO₄)₂(H₂SO₄) crystallizes isotypic to Na₂(HSO₄)₂(H₂SO₄). The coordination number of silver is 6 + 1. The structure of Ag₂(HSO₄)₂(H₂SO₄) is characterized by hydrogen bonded trimers of HSO₄^– tetrahedra, which are further connected to chains. For the recently published structure of AgHSO₄ the hydrogen bonding system was discussed. There are tetrameres and chains, connected by bifurcated hydrogen bonds. The structure of Hg₂(HSO₄)₂ contains Hg₂²⁺ cations with Hg–Hg distance of 2.509 Å. Every mercury atom is coordinated by one oxygen atom at shorter distance (2.18 Å) and three ones at longer distances (2.57 to 3.08 Å). The HSO₄^– tetrahedra form zigzag chains by hydrogen bonds.     

Synthese und Kristallstruktur von K2(HSO4)(H2PO4), K4(HSO4)3(H2PO4) und Na(HSO4)(H3PO4)

Synthesis and Crystal Structure of K₂(HSO₄)(H₂PO₄), K₄(HSO₄)₃(H₂PO₄), and Na(HSO₄)(H₃PO₄) Mixed hydrogen sulfate phosphates K₂(HSO₄)(H₂PO₄), K₄(HSO₄)₃(H₂PO₄) and Na(HSO₄)(H₃PO₄) were synthesized and characterized by X‐ray single crystal analysis. In case of K₂(HSO₄)(H₂PO₄) neutron powder diffraction was used additionally. For this compound an unknown supercell was found. According to X‐ray crystal structure analysis, the compounds have the following crystal data: K₂(HSO₄)(H₂PO₄) (T = 298 K), monoclinic, space group P 2₁/c, a = 11.150(4) Å, b = 7.371(2) Å, c = 9.436(3) Å, β = 92.29(3)°, V = 774.9(4) ų, Z = 4, R₁ = 0.039; K₄(HSO₄)₃(H₂PO₄) (T = 298 K), triclinic, space group P 1, a = 7.217(8) Å, b = 7.521(9) Å, c = 7.574(8) Å, α = 71.52(1)°, β = 88.28(1)°, γ = 86.20(1)°, V = 389.1(8)ų, Z = 1, R₁ = 0.031; Na(HSO₄)(H₃PO₄) (T = 298 K), monoclinic, space group P 2₁, a = 5.449(1) Å, b = 6.832(1) Å, c = 8.718(2) Å, β = 95.88(3)°, V = 322.8(1) ų, Z = 2, R₁ = 0,032. The metal atoms are coordinated by 8 or 9 oxygen atoms. The structure of K₂(HSO₄)(H₂PO₄) is characterized by hydrogen bonded chains of mixed H_nS/PO₄^– tetrahedra. In the structure of K₄(HSO₄)₃(H₂PO₄), there are dimers of H_nS/PO₄^– tetrahedra, which are further connected to chains. Additional HSO₄^– tetrahedra are linked to these chains. In the structure of Na(HSO₄)(H₃PO₄) the HSO₄^– tetrahedra and H₃PO₄ molecules form layers by hydrogen bonds.     

Synthese und Kristallstruktur von Tetraphenylphosphonium-Aquabis(tetrasulfido)thionitrosyl-Osmat,PPh4[Os(NS)(S4)2(H2O)]

Synthesis and Crystal Structure of Tetraphenylphosphonium Aqua-bis(tetrasulfido)thionitrosyl Osmate, PPh₄[Os(NS)(S₄)₂(H₂O)] PPh₄[Os(NS)(S₄)₂(H₂O)] has been prepared as redbrown crystals by reacting PPh₄[OsNCl₄] with a solution of excess disodium tetrasulfide in dimethylformamide/H₂O and characterized by IR spectroscopy and by a crystal structure determination. Space group P2₁/n, Z = 4, structure solution with 4162 independent reflections, R = 0.059 for reflections with I > 2σ(I). Lattice dimensions at ?40°C: a = 1138.9(5), b = 1301.4(4), c = 2092.7(7) pm, β = 104.74(3)º. Os? N, Os? O, and Os? S distances are 175.2(12), 219.8(12), and 237.5(4)?239.1(4) pm, respectively. The Os?N?S moiety is approximately linear, with an OsNS angle of 171.2(7)º.     

Synthese,Kristallstruktur und Festkörper-NMR-spektroskopische Untersuchungen von K5H(CN2)3

Synthesis, Crystal Structure, and Solid State MAS-NMR Spectroscopic Investigation of K₅H(CN₂)₃ Single phase K₅H(CN₂)₃ was synthesized by reaction of KHCN₂ with metallic potassium in liquid ammonia or by reaction of KNH₂ with melamine C₃N₃(NH₂)₃ at 320 °C, respectively. The crystal structure was determined from X-ray powder and single crystal data: K₅H(CN)₃, space group Im3m, a = 795.68(7) pm, Z = 2, R1 = 0.025, wR2 = 0.0438. In the solid K₅H(CN₂)₃ contains K⁺ and CN₂^2–, the anions exhibit D_∞h symmetry. According to ¹H and ¹³C solid state MAS-NMR investigations, temperature dependent impedance spectroscopy, and FTIR spectroscopy the protons are only loosely bound to the CN₂^2– ions. The proton conductivity shows a sharp increase above 70 °C.     

Ein neues Kaliumhydrogensulfat,K(H3O)(HSO4)2 — Synthese und Struktur

A New Potassium Hydrogensulfate, K(H₃O)(HSO₄)₂ — Synthesis and Structure Single crystals of the new compound K(H₃O)(SO₄)₂ are synthesized from the system potassium sulfate/sulfuric acid. The up to day not described compound crystallizes in the monoclinic space group P2₁/c with the unit cell parameters a = 7.203(1) b = 13.585(2) and c = 8.434(1) Å, β = 105.54(1)°, V = 795.1 ų, Z = 4 and D_x = 2.107 g · cm^?3. There are two crystallographically different tetrahedral SO₃(OH) anions. The first kind S1 tetrahedra forms dimers, whereas the second kind S2 forms infinite chains bonded via hydrogen bridges. The S1 dimers are linked to the S2 chains via oxonium ions (hydrogen bonds). Potassium is coordinated by 8 oxygen atoms which belong to four different SO₃(OH) tetrahedra. These potassium oxygen polyhedra are connected by common edges forming chains running parallel z.     

Ein neues Lithiumhydrogensulfat,Li2(HSO4)2(H2SO4) – Synthese und Kristallstruktur

A New Lithium Hydrogen Sulfate, Li₂(HSO₄)₂(H₂SO₄) – Synthesis and Crystal Structure The title compound crystallizes in good shaped single crystals from the system lithium sulfate/sulfuric acid in the orthorhombic space group Pccn, unit cell parameters a = 17.645(4), b = 5.378(1), c = 10.667(3) Å. V = 1 012.2 ų, Z = 4, D_x = 2.009 g cm^?3. There are two types of SO₄ tetrahedra, SO₃(OH) and SO₂(OH)₂, connected via hydrogen bonds forming layers parallel to the xy-plane. The layers are linked by Li atoms, which are tetrahedral coordinated by O atoms coming two by two from neighboured layers.     

Synthese und Kristallstruktur von [KNPPh3]6 · 4 C7H8

Synthesis and Crystal Structure of [KNPPh₃]₆ · 4 C₇H₈ [KNPPh₃]₆ · 4 C₇H₈ ( 1 ) has been prepared from HNPPh₃ and potassium hydride in boiling toluene forming pale yellow moisture sensitive crystals, which were characterized by a crystal structure determination. Space group P1, Z = 2, lattice dimensions at –83 °C: a = 1517.9(2), b = 1894.0(2), c = 2150,4(2) pm, α = 84.39(1)°, b = 89.31(1)°, c = 89.97(1)°, R₁ = 0.0684. 1 forms a K₆N₆ skeleton of a double cube with a common face of two K and two N atoms, the latter being fivefold coordinated by four K atoms and the P atom of the PPh₃ groups.     

Synthese und Struktur neuer Natriumhydrogensulfate Na(H3O)(HSO4)2; Na2(HSO4)2(H2SO4) und Na(HSO4)(H2SO4)2

Synthesis and Structure of New Sodium Hydrogen Sulfates Na(H₃O)(HSO₄)₂, Na₂(HSO₄)₂(H₂SO₄), and Na(HSO₄)(H₂SO₄)₂ Three acidic sodium sulfates have been synthesized from the system sodium sulfate/sulfuric acid and have been crystallographically characterized. Na(H₃O)(HSO₄)₂ ( A ) crystallizes in the space group P2₁/c with the unit cell parameters a = 6.974(2), b = 13.086(2), c = 8.080(3) Å, α = 105.90(4)°, V = 709.1 Å3, Z = 4. Na₂(HSO₄)₂(H₂SO₄) ( B ) is orthorhombic (space group Pna2₁) with the unit cell parameters a = 9.970(2), b = 6.951(1), c = 13.949(3) Å, V = 966.7 ų and Z = 4. Na(HSO₄)(H₂SO₄)₂ ( C ) crystallizes in the triclinic space group P1 with the unit cell parameters a = 5.084(1), b = 8.746(1), c = 11.765(3) Å, α = 68.86(2)°, β = 88.44(2)°, γ = 88.97(2)°, V = 487.8 Å3 and Z = 2. All three compounds contain SO₄ tetrahedra as HSO₄^? anions and additionally in B and C in form of H₂SO₄ molecules. The ratio H:SO₄ determines the connectivity degree in the hydrogen bond system. In A , there are zigzag chains and dimers additionally connected via oxonium ions. Complex chains consisting of cyclic trimers (two HSO₄^? and one H₂SO₄) are present in B . In structure C , several parallel chains are connected to columns due to the greater content of H₂SO₄. Sodium cations show a distorted octahedral coordination by oxygen in all three structures, the NaO₆ octahedra being “isolated” (connected via SO₄ tetrahedra only) in A . Pairs of octahedra with common edge form Na₂O₁₀ dimeric units in C . Such double octahedra are connected via common corners forming zigzag chains in B .     

Kaliumtriamidostannat(II), K[Sn(NH2)3] – Synthese und Kristallstruktur

Potassium Triamidostannate(II), K[Sn(NH₂)₃] – Synthesis and Crystal Structure Rusty‐red crystals of K[Sn(NH₂)₃] were obtained by the reaction of SnBr₂ and KNH₂ in a 1 : 3 molar ratio in liquid ammonia at 233 K in the form of platelets. The structure was determined from single crystal X‐ray diffractometer data: Space group P3; Z = 2; a = 6.560(1) Å, c = 7.413(2) Å. The structure contains trigonal pyramidal complex anions [Sn(NH₂)₃]^– and potassium cations. These ions are arranged to one another following the motif of a strongly distorted hexagonal close packing of sequence A(Sn) B(Sn) A′(K) B′(K) …     

Synthese,Kristallstruktur und Magnetismus von Natriumtetrachlorotitanat(II), Na2TiCl4

Synthesis, Crystal Structure and Magnetism of Sodium Tetrachlorotitanate(II), Na₂TiCl₄ Na₂TiCl₄ is obtained as single crystals by metallothermic reduction of TiCl₃ with sodium (525°C, 90 d, Ta container). Pure powder samples may be prepared by synproportionation of TiCl₃ with Ti in the presence of NaCl (950–520°C, 21 d). The structure refinement from four-circle diffractometer data confirms that Na₂TiCl₄ is isotypic with Sr₂PbO₄ (orthorhombic, space group Pbam (No. 55), Z = 2 a = 694.2(1), b = 1 198.9(2), c = 385.6(1) pm, R = 0.055, R_w = 0,038). Ti²⁺ is surrounded by a distorted octahedron of Cl^?. The octahedra are connected via common edges to chains, [TiCl_2/1Cl_4/2]^2?, that run in the [001] direction. Magnetic susceptibility data were recorded in the 2 to 300 K temperature range at various field strengths. The interpretation of the data was carried out with the aid of crystal-field calculations taking magnetic interactions into account. The non-Curie behaviour of the reciprocal magnetic susceptibility of Ti²⁺ in Na₂TiCl₄ is due to the influence of spin-obit coupling.     

Synthese und Kristallstruktur der Rhenium(VII)‐Nitridchloride ReNCl4 und ReNCl4·H2O

Syntheses and Crystal Structures of the Rhenium(VII) Nitride Chlorides ReNCl₄ and ReNCl₄·H₂O Rhenium(VII) nitride chloride, ReNCl₄ ( 1 ) is obtained in form of brown needles with metallic luster by the reaction of ReCl₅ with Cl₃VNCl at 140 °C under vacuum in a sealed glass ampoule. It crystallizes in the tetragonal space group I4 with the lattice parameters a = 826.7(4), c = 405.1(2) pm, and Z = 2. The square pyramidal molecules are connected by asymmetric nitrido bridges to form chains along the crystallographic c axis. The shorter Re‐N distance of 163.0(5) pm corresponds to a triple bond, while the pronounced longer distance of 242.0(5) pm can be interpreted with a weak donor bond. The reaction of ReCl₅ with VN at 170 °C under vacuum in a sealed glass ampoule yields red needles of ReNCl₄·H₂O ( 2 ). It crystallizes in the orthorhombic space group Pnma with a = 1075.4(2), b = 1108.5(2), c = 547.7(5) pm and Z = 4. The Re atoms exhibit a distorted octahedral coordination with the aqua ligand in trans position to the nitrido ligand. The Re‐N triple bond has a bond distance of 166.1(11) pm. The complexes are connected by hydrogen bridges O‐H···N to form chains.     

Synthese und Struktur von K[Au(AuCl)(AuPPh3)8)](PF6)2

Synthesis and Structure of K[Au(AuCl)(AuPPh₃)₈)](PF₆)₂ Photolysis of a mixture of Ph₃PAuCl and Ph₃PAuN₃ (1 : 3) in toluene/THF yields in the presence of Na₂[(C₅H₅)V(CO)₃] the new cluster cation [Au(AuCl)(AuPPh₃)₈]⁺. It crystallizes from CH₂Cl₂ after addition of KPF₆ as K[Au(AuCl)(AuPPh₃)₈](PF₆)₂ · 4 CH₂Cl₂. The compound forms a tetragonal structure with the space group P4/n and a = 2552.6(3), c = 1401.1(1) pm, Z = 2. The cluster cations with a spheroidal topology are built up of a centered Au₈ crown whose central gold atom in addition binds a AuCl group. The cluster occupies with its center and AuCl group a fourfold axis of the space group. The radial bonds between the central and the peripheral Au atoms are in the range of 263.7 to 268.4 pm, while the distances between the peripheral atoms are longer with 291.7 to 350.9 pm.     

Synthese und Kristallstruktur von [Na(12-Krone-4)2]2[Hg(Se4)2] · 1,5 DMF

Synthesis and Crystal Structure of [Na(12-Crown-4)₂]₂[Hg(Se₄)₂] · 1.5 DMF . The title compound has been prepared by the reaction of Na₂Se₄ with mercury acetate in DMF solution in the presence of 15-crown-5, forming dark red crystal needles. [Na(12-crown-4)₂]₂[Hg(Se₄)₂] · 1.5 DMF crystallizes in the space group C2/c with eight formula units per unit cell. The structure was determined with 3 824 observed unique reflections, R = 0.085. Lattice dimensions at - 70°C: a = 2 884(2), b = 1 407.7(7), c = 2 843(2) pm, β = 93.93(5)°. The structure consists of [Na(12-crown-4)₂]⁺ ions with a sandwichlike coordination of the crown ether molecules, and of [Hg(Se₄)₂]^2? ions, in which the mercury atom is coordinated by two tetraselenido ions in a chelating fashion. The [Hg(Se₄)₂]^2? ions are arranged to infinite chains via Se…?Se contacts.     

Synthese und Kristallstruktur von Hydrogenselenaten zweiwertiger Metalle – M(HSeO4)2 (M = Mg,Mn, Zn) und M(HSeO4)2 · H2O (M = Mn,Cd)

Synthesis and Crystal Structure of Hydrogen Selenates of Divalent Metals – M(HSeO₄)₂ (M = Mg, Mn, Zn) and M(HSeO₄)₂ · H₂O (M = Mn, Cd) New hydrogen selenates M(HSeO₄)₂ (M = Mg, Mn, Zn) and M(HSeO₄)₂ · H₂O (M = Mn, Cd) have been synthesized using MSeO₄ (M = Mg, Mn, Zn, Cd) and 90% selenic acid as starting materials. The crystal structures have been determined by X-ray single crystal crystallography. The compounds M(HSeO₄)₂ (M = Mg, Zn) belong to the structure type of Mg(HSO₄)₂, whereas Mn(HSeO₄)₂ forms a new structure type. Both hydrogen selenate monohydrates are isotypic to Mg(HSO₄)₂ · H₂O. In all compounds the metal atoms are octahedrally coordinated by oxygen atoms of different HSeO₄-tetrahedra. In the HSeO₄-tetrahedra the Se–OH-distances (mean value 1.70 Å) are about 0.1 Å longer than Se–O-distances (mean value 1.62 Å). In the structure of M(HSeO₄)₂ (M = Mg, Zn) there are zigzag chains of hydrogen bonded HSeO₄-tetrahedra. The structure of Mn(HSeO₄)₂ is characterized by chains of HSeO₄-tetrahedra in form of screws. Hydrogen bonds from and to water molecules connect double layers of MO₆-octahedra and HSeO₄-tetrahedra in the structures of M(HSeO₄)₂ · H₂O.     

Synthese und Kristallstruktur des Nonaselenids [Sr(15-Krone-5)2]Se9

Synthesis and Crystal Structure of the Nonaselenide [Sr(15-crown-5)₂]Se₉ The title compound was prepared by the reaction of excess selenium with strontium diselenide in DMF in the presence of 15-crown-5. [Sr(15-crown-5)₂]Se₉ forms black crystals, which are soluble in DMF. They were characterized by FIR spectroscopy and by an X-ray structure determination. Space group P2₁/n, Z = 4, 2 381 observed unique reflections, R = 0.073. Lattice dimensions at 19°C: a = 1 228.7, b = 1 893.4, c = 1 575.7 pm, β = 99.15°. The compound consists of [Sr(15-crown-5)₂]²⁺ ions in which the strontium ion is coordinated by the oxygen atoms of the crown ether molecules in a sandwich-like fashion, and of Se₉^2? ions with a chain structure, which has a topolocical resemblance with the bicyclic ion Se.     

Synthese und Kristallstruktur von (C5H5)Mo(CO)3(AuPPh3) und [(C5H5)Mo(CO)2(AuPPh3)4]PF6

Synthesis and Crystal Structure of (C₅H₅)Mo(CO)₃(AuPPh₃) and [(C₅H₅)Mo(CO)₂(AuPPh₃)₄]PF₆ CpMo(CO)₃(AuPPh₃) is obtained by the reaction of Li[CpMo(CO)₃] with Ph₃PAuCl at ?95°C in CH₂Cl₂. It crystallizes in the monoclinic space group C2/c with a = 2625.1(7), b = 883.2(1), c = 2328.4(7) pm, β = 116.39(1)° und Z = 8. In the complex the AuPPh₃ group is coordinated to the CpMo(CO)₃ fragment with a Au? Mo bond of 271,0 pm. The Mo atom thus achieves a square pyramidal coordination with the center of the Cp ring in apical position. CpMo(CO)₃(AuPPh₃) reacts under uv irradiation with an excess of Ph₃PAuN₃ to afford the cluster cation [CpMo(CO)₂(AuPPh₃)₄]⁺. It crystallizes as [CpMo(CO)₂(AuPPh₃)₄]PF₆ · 2 CH₂Cl₂ in the orthorhombic space group P2₁2₁2₁ with a = 1553.9(1), b = 1793.8(2), c = 2809.8(7) pm und Z = 4. The five metal atoms form a trigonal bipyramidal cluster skeleton with the Mo atom in equatorial position. The Mo? Au distances range from 275.5 to 280.8 pm, and the Au? Au distances are between 281.2 and 285.6 pm.     

Synthese und Kristallstruktur des Selenyl-Phosphaniminato-Komplexes SeO(NPPh3)2

Synthesis and Crystal Structure of the Selenyl-Phosphoraneiminato Complex SeO(NPPh₃)₂ SeO(NPPh₃)₂ has been prepared from SeO₂ and Me₃SiNPPh₃ in a SeO₂ suspension in acetonitrile, forming colourless crystals. The compound is characterized by IR spectroscopy and by a crystal structure determination. Space group P1 , Z = 2, structure solution with 5 344 observed unique reflections, R = 0.064. Lattice dimensions at ?40°C: a = 931.6, b = 947.6, c = 1 762 pm, α = 77.50°, β = 81.78°, γ = 79.23°. The compound forms monomeric molecules in which the selenium atom is φ-tetrahedrally surrounded with bond lengths SeO = 161.7 pm and SeN = 179.9 and 181.6 pm.     

Synthese und Kristallstruktur von LiHSO4

Synthesis and Crystal Structure of LiHSO₄ Single crystals of the new compound LiHSO₄ are synthezised from the system Lithiumsulfate/Sulfuric acid. The up to day not determined structure of the title compound is monoclinic, space group P2₁/c with the lattice constants a = 5.234(2), b = 7.322(1) and c = 8.363(1) Å, b? = 90.02(2)°. The volume of the unit cell has been determined to V = 320.5 ų, the number of formula units to Z = 4 and the density to D_x = 2.156 g cm^?3. There are crystallographically identical SO₃(OH)- and LiO₄-tetrahedra in the structure. Every tetraheda is linked to four different tetrahedra of the other sort. Two neighboured LiO4 terahedra form a common edge. In that way layers are formed running parallel the yz-plane. These layers are connected over hydrogen bonds.     

Synthese,Kristallstruktur und Schwingungsspektren von Dimethylphosphoniumtetrachloroaluminat,H2PMe2+AlCl4–

Synthesis, Crystal Structure, and Vibrational Spectra of Dimethylphosphonium Tetrachloroaluminate, H₂PMe₂⁺AlCl₄^– H₂PMe₂⁺AlCl₄^– was synthesized by the reaction of Me₂PH with HCl and AlCl₃ in CH₂Cl₂. The structure of the compound was determined by X‐ray structure determination. H₂PMe₂⁺AlCl₄^– crystallizes in the monoclinic space group P2₁/c with a = 14.445(1), b = 11.344(1) and c = 12.394(1) Å, β = 90.00(1)°, with 8 formula units per unit cell. The frequencies obtained by Raman and infrared spectroscopy were assigned to the normal modes of the H₂PMe₂⁺ and AlCl₄^– units.     

Sulfate und Hydrogensulfate des Erbiums: Er(HSO4)3-I,Er(HSO4)3-II,Er(SO4)(HSO4) und Er2(SO4)3

Sulfates and Hydrogensulfates of Erbium: Er(HSO₄)₃-I, Er(HSO₄)₃-II, Er(SO₄)(HSO₄), and Er₂(SO₄)₃ Rod shaped light pink crystals of Er(HSO₄)₃-I (orthorhombic, Pbca, a = 1195.0(1) pm, b = 949.30(7) pm, c = 1644.3(1) pm) grow from a solution of Er₂(SO₄)₃ in conc. H₂SO₄ at 250 °C. From slightly diluted solutions (85%) which contain Na₂SO₄, brick shaped light pink crystals of Er(HSO₄)₃-II (monoclinic, P2₁/n, a = 520.00(5) pm, b = 1357.8(1) pm, c = 1233.4(1) pm, β = 92.13(1)°) were obtained at 250 °C and crystals of the same colour of Er(SO₄)(HSO₄) (monoclinic, P2₁/n, a = 545.62(6) pm, b = 1075.6(1) pm, c = 1053.1(1) pm, β = 104.58(1)°) at 60 °C. In both hydrogensulfates, Er³⁺ is surrounded by eight oxygen atoms. In Er(HSO₄)₃-I layers of HSO₄^– groups are connected only via hydrogen bridges, while Er(HSO₄)₃-II consists of a threedimensional polyhedra network. In the crystal structure of Er(SO₄)(HSO₄) Er³⁺ is sevenfold coordinated by oxygen atoms, which belong to four SO₄^2–- and three HSO₄^–-tetrahedra, respectively. The anhydrous sulfate, Er₂(SO₄)₃, cannot be prepared from H₂SO₄ solutions but crystallizes from a NaCl-melt. The coordination number of Er³⁺ in Er₂(SO₄)₃ (orthorhombic, Pbcn, a = 1270.9(1) pm, b = 913.01(7) pm, c = 921.67(7) pm) is six. The octahedral coordinationpolyhedra are connected via all vertices to the SO₄^2–-tetrahedra.