Dihydro[2.2.2]cryptand di‐μ‐hydroxo‐bis[bis(nitrato‐κ2O,O′)dioxouranium(VI)] monohydrate

In the title dinuclear uranyl complex, (C₁₈H₃₈N₂O₆)[(UO₂)₂(NO₃)₄(OH)₂]·H₂O, each pair of uranyl ions in the two independent centrosymmetric dianionic dimers is bridged by the two hydroxide ions, with the nitrate ions ensuring equatorial hexagonal coordination. The di­hydro[2.2.2]­cryptand (4,7,13,16,21,24‐hexaoxa‐1,10‐diazabicyclo[8.8.8]­hexa­cosane) dication presents an `in–in' conformation (endo protonation) and it is hydrogen bonded to the hydroxide ions, either directly or via a water mol­ecule, resulting in the formation of linear hydrogen‐bonded polymers.     

A Tetrahomodioxacalix[6]arene as a Ditopic Ligand for Uranyl Ions with Carbonate or Carbamate Bridges

The first crystal structures of a p-tert-butyltetrahomodioxacalix[6]arene comprising two tri-phenolic subunits separated by two ether bridges and two of its complexes with uranyl ions are reported. The doubly deprotonated macrocycle assumes a much elongated, cone-like conformation including two organic species. Two binuclear uranyl complexes are described. In both, each cation is bound to the three phenoxide oxygen atoms of a tri-phenolic subunit and to a central, bridging, carbonate or carbamate ion. The formation of the latter ions from the amines used as bases is discussed.     

Structural Diversity of Sheets in Rubidium Uranyl Oxoselenates: Synthesis and Crystal Structures of Rb2[(UO2)(SeO4)2(H2O)](H2O), Rb2[(UO2)2(SeO4)3(H2O)2](H2O)4, and Rb4[(UO2)3(SeO4)5(H2O)]

Single crystals of three rubidium uranyl selenates, Rb₂[(UO₂)(SeO₄)₂(H₂O)](H₂O) ( 1 ), Rb₂[(UO₂)₂(SeO₄)₃(H₂O)₂](H₂O)₄ ( 2 ), and Rb₄[(UO₂)₃(SeO₄)₅(H₂O)] ( 3 ), have been prepared by evaporation from aqueous solutions made out of mixtures of uranyl nitrate, selenic acid and Rb₂CO₃. The structures of all compounds have been solved by direct methods on the basis of X‐ray diffraction data sets. The crystallographic data are as follows: ( 1 ): orthorhombic, Pna2₁, a = 13.677(2), b = 11.8707(13), c = 7.6397(9) Å, V = 1240.4(3) ų, R₁ = 0.045 for 2396 independent observed reflections; ( 2 ): triclinic, P1¯, a = 8.4261(12), b = 11.8636(15), c = 13.3279(18) Å, α = 102.612(10), β = 107.250(10), γ = 102.510(10)°, V = 1183.7(3) ų, R₁ = 0.067 for 4762 independent observed reflections; ( 3 ): orthorhombic, Pbnm, a = 11.3761(14), b = 15.069(2), c = 19.2089(17) Å, V = 3292.9(7) ų, R₁ = 0.075 for 3808 independent observed reflections. The structures of the phases 1 , 2 , and 3 are based upon uranyl selenate hydrate sheets composed from corner‐sharing pentagonal [UO₇]^8— bipyramids and [SeO₄]^2— tetrahedra. In the crystal structure of 1 , the sheets have composition [(UO₂)(SeO₄)₂(H₂O)]^2— and run parallel to (001). The interlayer contains Rb⁺ cations and additional H₂O molecules. In structure of 2 , the [(UO₂)₂(SeO₄)₃(H₂O)₂]^2— sheets are oriented parallel to (101). Highly disordered Rb⁺ cations and H₂O molecules are located between the sheets. The structure of 3 is based upon [(UO₂)₃(SeO₄)₅(H₂O)]^4— sheets stacked parallel to (010) and contains Rb⁺ cations in the interlayers. The topologies of the uranyl oxoselenate sheets observed in the structures of 1 , 2 , and 3 are related to the same simple and highly‐symmetric graph consisting of 3‐connected white and 6‐connected black vertices.     

Synthesis and X-ray and Spectral Study of the Compounds [Q4N]2[Fe2(S2O3)2(NO)4] (Q = Me,Et, n-Pr,n-Bu)

Iron nitrosyl complexes with general formula [Q₄N]₂[Fe₂(S₂O₃)₂(NO)₄] (Q = Me, Et, n-Pr, n-Bu) were synthesized by the exchange reaction of K₂[Fe₂(S₂O₃)₂(NO)₄] with tetraalkylammonium bromides. The molecular and crystal structure of [(CH₃)₄N]₂[Fe₂(S₂O₃)₂(NO)₄] were studied by X-ray diffraction analysis. The iron atom in the four-membered cycle of the [2Fe–2S] anion is bound to another Fe atom and to two sulfur atoms and is coordinated by two nonequivalent NO groups, each bridging sulfur atom being bound to the SO₃group. The structurally equivalent iron atoms are in the state Fe^1–(S= 1/2). The Mössbauer spectroscopy method shows that the complexes are diamagnetic due to the strong Fe–Fe bond. It is found that the SO₃group provides higher stability of the thiosulfate anion than the anion in Roussin's red salt [Fe₂S₂(NO)₄]^2–.     

Metal Complexes with Macrocyclic Ligands. Part XXXIX. Mono- and binuclear copper(II) complexes of a bridging bis[1, 4, 7-triazacyclononane]

The new bis-macrocycle 1, 1′-[(1H-pyrazol-3], 5-diyl)bis(methylene)bis[1, 4, 7-triazacyclononane] ( 1 ) was synthesized and its complexation with Cu²⁺ studied. Potentiometric and spectrophotometric titrations indicate that, in addition to the mononuclear species [Cu(LH₂)]⁴⁺, [Cu(LH)]³⁺, [CuL]²⁺, and [Cu(LH_?1)]⁺, binuclear complexes such as [Cu₂L]⁴⁺, [Cu₂(LH_?1)]³⁺, and [Cu₂(LH_-2)]²⁺ are also formed in solution. The stability constants and spectral properties of these are reported. The binuclear species [Cu₂(LH_?1)]³⁺ specifically reacts with an azide ion to give a ternary complex [Cu₂(LH_?1)(N₃)]²⁺, the stability and structure of which were determined spectrophotometrically and by X-ray diffraction, respectively. The two Cu²⁺ ions are in a square-pyramidal coordination geometry. The axial ligand is one of the N-atoms of the 1, 4, 7-triazacyclononane ring, whereas at the base of the square pyramid, one finds the other two N-atoms of the macrocycle, one N-atom of the pyrazolide and one of the azide, both of which are bridging the two metal centres. In [Cu₂(LH_?1)(N₃)]²⁺, a strong antiferromagnetic coupling is present, thus resulting in a species with a low magnetic moment of 1.36 B.M. at room temperature.     

Isopropylammonium Layered Uranyl Chromates: Syntheses and Crystal Structures of [(CH3)2CHNH3]3[(UO2)3(CrO4)2O(OH)3] and[(CH3)2CHNH3]2[(UO2)2(CrO4)3(H2O)]

Two novel isopropylamine‐templated uranyl chromates, [(CH₃)₂CHNH₃]₃[(UO₂)₃(CrO₄)₂O(OH)₃] ( 1 ) and [(CH₃)₂CHNH₃]₂[(UO₂)₂(CrO₄)₃(H₂O)] ( 2 ) were prepared by hydrothermal method at 100 °C. The compounds were characterized by electron microprobe analysis and X‐ray diffraction crystal structure analysis [ 1 : trigonal, P31m, a = 9.646(4), c = 8.469(4) Å, V = 682.4(5) ų; 2 : monoclinic, P2₁/c, a = 11.309(3), b = 11.465(3), c = 17.055(5) Å, β = 99.150(6)°, V = 2183.2(11) ų]. The structure of 1 is based upon trimers of uranyl bipyramids interlinked by CrO₄ tetrahedra to form [(UO₂)₃(CrO₄)₂O(OH)₃]^3– layers, whereas, in the structure of 2 , UO₇ and UO₆(H₂O) pentagonal bipyramids are linked through CrO₄ tetrahedra into the [(UO₂)₂(CrO₄)₃(H₂O)]^2– layers. The structures show many similarities to related uranyl selenate compounds, thus providing additional data on similarities and differences between uranyl sulfates, chromates, selenates, and molybdates.     

Synthesis and Complexation of 1,2-Bis[(monoaza[15]crown-5)-N-yl]glyoxime. Crystal Structure of (1,2-Bis[(monoaza[15]crown-5)-N-yl]glyoximato)palladium(II)

A new vicinal dioxime ligand with two crown-ether groups, 1,2-bis[(monoaza[15]crown-5)-N-Yl]-glyoxime(LH₂), has been prepared from cyanogen di-N-oxide and monoaza[15]crown-5. Ni(II), Pd(II), and Pt(IV) complexes of LH₂ with or without alkali-metal ions bound to macrocyclic groups have been isolated. The high affinity of [Pd(LH)₂] and [Ni(LH)₂] for the K⁺ ion is observed in solvent extraction experiments. A single-crystal X-ray structure confirms the postulated geometry of [Pd(LH)₂]- The Pd-atom of the centro-symmetric molecule has square-planar PdN₄ coordination where Pd–N distances range from 1.978(3) to 1.970(3) Å. The N–Pd–N intraligand angle is 79.9(1)^°.     

Syntheses and structures of two new uranyl complexes [UO2(DPDPU)2(NO3)2](C6H5CH3) and [UO2(PMBP)2(DPDPU)](CH3C6H4CH3)0.5

Two new uranyl complexes [UO₂(DPDPU)₂(NO₃)₂](C₆H₅CH₃) (1) and [UO₂(PMBP)₂ (DPDPU)](CH₃C₆H₄CH₃)_0.5 (2), (DPDPU?=?N,N′-dipropyl-N,N′-diphenylurea, HPMBP?= 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5) were synthesized and characterized. The coordination geometry of the uranyl atom in 1 is distorted hexagonal bipyramidal, coordinated by two oxygen atoms of two DPDPU molecules and four oxygen atoms of two bidentate nitrate groups. The coordination geometry of the uranyl atom in 2 is distorted pentagonal bipyramidal, coordinated by one oxygen atom of one DPDPU molecule and four oxygen atoms of two chelating PMBP molecules.     

Structural Investigations and Thermal Behavior of (NH4)[Cr(C2O4)2]·2H2O

Single crystals of ammonium chromium(III) dioxalate dihydrate (or ammonium diaquo bis(μ‐oxalato)chromate(III)) have been obtained from aqueous solution of oxalic acid and ammonium dichromate. A pale violet crystal of good optical quality was used for the structure determination at ?100(2) and 25(2) °C, respectively. The basic crystallographic data for the low temperature data set are as follows: monoclinic, space group C2/m, a = 6.597(2) Å, b = 7.301(2) Å, c = 9.983(3) Å, β = 92.32(2)°, V = 480.5(2) ų. The structure was solved by direct methods and refined (using anisotropic displacement parameters for all non‐hydrogen atoms) to a final residual of R1 = 0.032 for 503 independent observed reflections (I>2σ(I)). The compound is isotypic with the corresponding rubidium salt. The structure is built up from alternating layers parallel to (001) containing (NH₄)⁺ ions or Cr(C₂O₄)₂(H₂O)₂ octahedra, respectively. The corners of the octahedra consist of four O atoms from two oxalate groups and two additional water molecules. The ammonium cations (occupying Wyckoff‐site 2a) are disordered among two possible orientations. They provide linkage between different octahedral layers by hydrogen bridging. The water molecules in turn form hydrogen bridges with adjacent octahedra within the same layer. Further structural characterization included infrared spectroscopy. According to DTA/TG experiments the present compound shows several thermal processes in the range between room temperature and 900 °C.     

Inclusion of diprotonated [2.2.2]cryptand in the cavity of uranyl‐complexed p‐phenyl­tetra­homodioxacalix[4]arene

In the title compound, 4,7,13,16,21,24‐hexa­oxa‐1,10‐diazo­nia­bicyclo­[8.8.8]hexa­cosane dioxo[7,13,21,27‐tetra­phenyl‐3,17‐di­oxa­penta­cyclo­[23.3.1.1^5,9.1^11,15.1^19,23]ditriaconta‐1(29),5,7,9(30),11(31),12,14,19(32),20,22,25,27‐dodeca­ene‐29,30,31,32‐tetra­olato]uranium dimethyl sulfoxide tri­solvate, (C₁₈H₃₈N₂O₆)[U(C₅₄H₄₀O₆)O₂]·3C₂H₆OS, the uranyl ion is bound to the four phenoxide groups of the deprotonated p‐phenyl­tetra­homodioxacalix[4]arene ligand in a cone conformation, resulting in a dianionic complex. The diprotonated [2.2.2]cryptand counter‐ion is located in the cavity defined by the eight aromatic rings of the homooxacalixarene, where it is held by cation–anion, cation–π and possibly C—H⋯π inter­actions. Dimerization in the packing leads to the formation of sandwich assemblages in which two diprotonated [2.2.2]cryptands are encompassed by two uranyl complexes.     

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.     

Double complexes [Co(NH3)5(H2O)]2[Zr3F18]·6H2O and [Co(NH3)6]2[Zr3F18]·6H2O

The structures of orthorhombic bis[pentaammineaquacobalt(III)] tetra‐μ₂‐fluorido‐tetradecafluoridotrizirconium(IV) hexahydrate (space group Ibam), [Co(NH₃)₅(H₂O)]₂[Zr₃F₁₈]·6H₂O, (I), and bis[hexaamminecobalt(III)] tetra‐μ₂‐fluorido‐tetradecafluoridotrizirconium(IV) hexahydrate (space group Pnna), [Co(NH₃)₆]₂[Zr₃F₁₈]·6H₂O, (II), consist of complex [Co(NH₃)_x(H₂O)_y]³⁺ cations with either m [in (I)] or and 2 [in (II)] symmetry, [Zr₃F₁₈]⁶⁻ anionic chains located on sites with 222 [in (I)] or 2 [in (II)] symmetry, and water molecules.     

f-Element/crown ether complexes, 11. Preparation and structural characterization of [UO2(OH2)5] [ClO4]2·3(15-crown-5)·CH3CN and [UO2(OH2)5] [ClO4]2·2(18-crown-6)·2 CH3CN·H2O

The reaction of UO₂(ClO₄)·nH₂O with 15-crown-5 and 18-crown-6 in acetonitrile yielded the title complexes. [UO₂(OH₂)₅] [ClO₄]₂·3(15-crown-5)·CH₃CN crystallizes in the triclinic space groupPT with (at–150°C)a=8.288(6),b=12.874(7),c=24.678(7) Å, =82.62(4), =76.06(5), =81.06(5)°, andD _calc=1.67 g cm^–3 forZ=2 formula units. Least-squares refinement using 6248 independent observed reflections [F _o5(F _o)] led toR=0.111. [UO₂(OH₂)₅] [ClO₄]₂·2(18-crown-6)·2CH₃CN·H₂O is orthorhombicP2₁2₁2₁ with (at–150 °C)a=12.280(2),b=17.311(7),c=22.056(3) Å,D _calc=1.68 g cm^–3,Z=4, andR=0.032 (3777 observed reflections). In each complex the crown ether molecules are hydrogen bonded to the water molecules of the pentagonal bipyramidal [UO₂(OH₂)₅]²⁺ ions, each crown ether having exclusive use of two hydrogen atoms from one water molecule and one hydrogen from another water molecule. In the 15-crown-5 complex the remaining hydrogen bonding interaction is between one of the water molecules and one of the perchlorate anions. The solvent molecule has a close contact between the methyl group and a perchlorate anion suggesting a weak interaction. There are a total of three U-OH...OClO₃ hydrogen bonds to the two perchlorate anions in [UO₂(OH₂)₅] [ClO₄]₂·(18-crown-6)·2CH₃CN ·H₂O. The remaining coordinated water hydrogen bond is to the uncoordinated 2H₂O molecule, which in turn is hydrogen bonded to a perchlorate oxygen atom and an acetonitrile nitrogen atom. One solvent methyl group interacts with an anion, the other with one of the 18-crown-6 molecules. Unlike the 15-crown-5 structure, the hydrogen bonding in this complex results in a polymeric network with formula units joined by hydrogen bonds from one of the solvent molecules and the uncoordinated water molecule. Supplementary data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82051 (37 pages).For Part 10, see reference [1].     

First‐ and second‐ sphere coordination of the uranyl ion by bis­[2‐(2‐hydroxy­phenoxy)­ethoxy]­ethane

Uranyl nitrate hexahydrate reacts with bis­[2‐(2‐hydroxy­phenoxy)­ethoxy]­ethane (C₁₈H₂₂O₆), denoted LH₂ hereafter, in the presence of triethylamine to give ­triethylammonium aqua[2,2′‐(3,6‐dioxaoctane‐1,8‐diyldioxy)diphenolato‐κ²O,O′](nitrato‐κ²O,O′)dioxouranium(VI), (Et₃NH)[UO₂(H₂O)L(NO₃)], which possesses a symmetry plane. The uranyl ion is coordinated to the two phenoxide O atoms, a nitrate ion and a water mol­ecule (first sphere); the water mol­ecule is itself held in the crown ether chain by hydrogen‐bonding interactions, thus ensuring second‐sphere coordination by the ligand L.     

The Rb analogue of grimselite,Rb6Na2[(UO2)(CO3)3]2(H2O)

The crystal structure of the Rb analogue of grimselite, rubidium sodium uranyl tricarbonate hydrate, Rb₆Na₂[(UO₂)(CO₃)₃]₂(H₂O), consists of a uranyl hexagonal bipyramid that shares three non‐adjacent equatorial edges with carbonate triangles, resulting in a uranyl tricarbonate cluster of composition [(UO₂)(CO₃)₃)]. These uranyl tricarbonate clusters form layers perpendicular to [001] and are interconnected by NaO₈ polyhedra. The title compound is isostructural with grimselite, with a reduced occupancy of the H₂O site (25% versus 50% in grimselite).     

Eine alternative Synthese des Oligoalumosiloxans [Ph2SiO]8[Al(O)OH]4 und seiner Alkohol‐Addukte

The oligoalumosiloxanes {[Ph₂SiO]₈[Al(O)OH]₄·2,5Et₂O·HOtBu} ( 6 ) and {[Ph₂SiO]₈[Al(O)OH]₄·2Et₂O·2HOiPr} ( 7 ) have been obtained from the reaction of diphenylsilanediol with aluminium‐tri‐tert‐butoxide and aluminium‐tri‐iso‐propoxide in ethyl ether with reasonable yields. In a 1:1 molar mixture of toluene and the respective alcohol (iso‐propanol or tert‐butanol), the ethyl ether molecules in {[Ph₂SiO]₈[Al(O)OH]₄·4Et₂O}, in 6 or 7 can be completely displaced forming the compounds [Ph₂SiO]₈[Al(O)OH]₄·4HOiPr ( 8 ) and [Ph₂SiO]₈[Al(O)OH]₄·nHOtBu ( 9 ). Whereas 6 , 7 and 8 are crystalline, 9 is obtained as a viscous liquid. An X‐ray structure determination on {[Ph₂SiO]₈[Al(O)OH]₄·3Et₂O·HOtBu} reveals different bonding modes of the diethyl ether molecules to the oligoalumosiloxane compared to the tert‐butanol, which forms two hydrogen bonds (one to the OH‐group of the inner Al₄(OH)₄ cycle and one through the alcohol OH‐group to a Si–O–Al moiety. The alcohol adducts have been characterized in solution through ¹H‐, ¹³C‐ and ²⁹Si‐NMR and show dynamic equilibria between the oligoalumosiloxane [Ph₂SiO]₈[Al(O)OH]₄ and the alcohol molecules.     

Oxomolybdenum(V) complexes of bis-(2-benzimidazolyl) alkanes

Summary Oxomolybdenum(V) complexes of the type (LH₄) [MoOCl₅] (where LH₂ = dimethylene bis-2-benzimidazole or tetramethylene bis-2-benzimidazole), [MoOCl₃(LH₂)] (where LH₂ = tetramethylene bis-2-benzimidazole), [(Mo₂O₄Cl₂-(H₂O)₃)₂(LH₂)] (where LH₂ = dimethylene bis-2-benzimidazole, tetramethylene bis-2-benzimidazole or hexamethylene bis-2-benzimidazole) and [Mo₂O₃Cl₄(LH₂)₂] (where LH₂ = tetramethylene bis-5-nitro-2-benzimidazole) were prepared and characterised. The mononuclear complexes show u.v.-vis. absorptions characteristic of octahedral molybdenum(V). The dinuclear complexes do not absorb in the visible region, possibly due to the presence of an Mo₂O ₄ ^{2 +}} core, which is also indicated by their diamagnetic behaviour. The biological activities of the free ligands and their complexes have been studied.     

Die Kristallstrukturen von trans‐[NiBr2(Pyridin)4] und [Ni(HNPEt3)4]I2

Crystal Structures of trans ‐[NiBr₂(pyridine)₄] and [Ni(HNPEt₃)₄]I₂ Turquoise single crystals of trans‐[NiBr₂(pyridine)₄] have been obtained by the reaction of excess pyridine with nickel(II) bromide/diacetonealcohol. According to the crystal structure determination the nickel atom is octahedrally coordinated by the two bromine atoms in trans‐position and by the nitrogen atoms of the pyridine molecules. Space group Pna2₁, Z = 4, lattice dimensions at 20 °C: a = 1592.9(2), b = 943.8(1), c = 1413.0(2) pm, R₁ = 0.0492. Dark blue single crystals of the phosphoraneimine complex [Ni(HNPEt₃)₄]I₂ have been obtained from NiI₂/H₂O with excess Me₃SiNPEt₃ and subsequent recrystallization from acetonitrile. According to the crystal structure determination the nickel atom is tetrahedrally coordinated by the nitrogen atoms of the HNPEt₃ molecules. The iodide ions are connected via N–H…I contacts with the cation to form an ion triple. Space group P2₁/c, Z = 4, lattice dimensions at –80 °C: a = 1934.9(2), b = 1078.3(1), c = 1966.3(2) pm, β = 111.040(8)°; R₁ = 0.043.     

Die Kristallstrukturen von {Li3(12-Krone-4)2[HC(CN)2]3}, {Na(15-Krone-5)-[HC(CN)2]} und {Na[N(nBu)4][HC(CN)2]2 · THF}

The Crystal Structures of {Li₃(12-crown-4)₂[HC(CN)₂]₃}, {Na(15-crown-5)[HC(CN)₂]}, and {NaN(nBu)₄[HC(CN)₂]₂ · THF} The preparation and the crystal structures of the title compounds 1 — 3 are described. 1 forms a polymeric chain structure, in which one of the lithium ions is linked by Li…NCC(H)CN… bridges. The remaining lithium ions form (12-crown-4)Li[NCC(H)CN] units, which are coordinated by one of the nitrogen atoms of the dicyanomethanide ions with the lithium ions of the chain. 2 forms an ion pair, in which the sodium ion is coordinated by the five oxygen atoms of the crown ether molecule and by one nitrogen atom of the dicyanomethanide ion. 3 has a threedimensional network, in which the sodium ions are coordinated in a distorted tetrahedral manner by the nitrogen atoms of the dicyanomethanide ions. In the cavities of the network the tetrabutylammonium ions and the THF molecules are found.     

Synthesis and Characterization of Gd2[Pt2(SO4)4(HSO4)2](HSO4)2

Red single crystals of Gd₂[Pt₂(SO₄)₄(HSO₄)₂](HSO₄)₂ (triclinic, , Z = 1, a = 844.02(9), b = 908.50(9), c = 939.49(8) pm, α = 107.73(1)°, β = 112.10(1)°, γ = 103.53(1)°) were obtained by the reaction of [Gd(NO₃)(H₂O)₇][PtCl₆]·4H₂O with sulfuric acid at 320 °C in a sealed glass ampoule. In the crystal structure, Pt₂ dumbbells are coordinated by four chelating sulfate groups and two monodentate hydrogensulfate ions. Two further HSO₄^? ions are not bonded to the Pt₂ dumbbell. The Gd³⁺ ions are eightfold coordinated by oxygen atoms. The IR data of Gd₂[Pt₂(SO₄)₄(HSO₄)₂](HSO₄)₂ are typical for these type of compounds. The thermal decomposition of the compound leads to elemental platinum and Gd₂O₃.