New Structure Type among Octahydrated Rare‐Earth Sulfates, β‐Ce2(SO4)3·8H2O,and a new Ce2(SO4)3·4H2O Polymorph

Syntheses, crystal structures and thermal behavior of two new hydrated cerium(III) sulfates are reported, Ce₂(SO₄)₃·4H₂O ( I ) and β‐Ce₂(SO₄)₃·8H₂O ( II ), both forming three‐dimensional networks. Compound I crystallizes in the space group P2₁/n. There are two non‐equivalent cerium atoms in the structure of I , one nine‐ and one ten‐fold coordinated to oxygen atoms. The cerium polyhedra are edge sharing, forming helically propagating chains, held together by sulfate groups. The structure is compact, all the sulfate groups are edge‐sharing with cerium polyhedra and one third of the oxygen atoms, belonging to sulfate groups, are in the S–Oμ₃–Ce₂ bonding mode. Compound II constitutes a new structure type among the octahydrated rare‐earth sulfates which belongs to the space group Pn. Each cerium atom is in contact with nine oxygen atoms, these belong to four water molecules, three corner sharing and one edge sharing sulfate groups. The crystal structure is built up by layers of [Ce(H₂O)₄(SO₄)]_nⁿ⁺ held together by doubly edge sharing sulfate groups. The dehydration of II is a three step process, forming Ce₂(SO₄)₃·5H₂O, Ce₂(SO₄)₃·4H₂O and Ce₂(SO₄)₃, respectively. During the oxidative decomposition of the anhydrous form, Ce₂(SO₄)₃, into the final product CeO₂, small amount of CeO(SO₄) as an intermediate species was detected.     

A pseudo‐merohedrally twinned rare‐earth sulfate: K6[Ce(HSO4)2(SO4)4]·H2O,a novel structure type

A novel structure type of an acidic rare‐earth sulfate, hexa­potassium cerium dihydrogensulfate tetra­sulfate monohydrate, is reported. The crystal is twinned, mimicking tetra­gonal symmetry. The Ce^IV atom is nine‐coordinate, connecting to one corner‐sharing and four edge‐sharing sulfate groups. One of the potassium ions is disordered over two general positions. The compound is unique as it contains rare‐earth monomers, [Ce(HSO₄)(SO₄)₄]⁵⁻. The structure is composed of these monomers, water mol­ecules, discrete hydrogensulfate ions and potassium ions held together by ionic inter­actions. There are two types of alternating layers in the structure, with compositions [K₄Ce(HSO₄)(SO₄)₄]⁻ and [K₂(HSO₄)(H₂O)]⁺.     

A new chromate of tetravalent cerium: Ce2(CrO4)4·2H2O

Dicerium(IV) tetrachromate(VI) dihydrate, Ce(CrO₄)₄·2H₂O, has been prepared from an acidic aqueous solution at room temperature. Its novel crystal structure, which was solved from single‐crystal X‐ray diffraction data, is built from isolated CrO₄ tetrahedra and isolated Ce(O,H₂O)_n (n = 8 and 9) polyhedra. All atoms are in general positions. The mean Ce—O and Cr—O bond lengths are 2.358 and 1.651 Å, respectively. Comparisons are drawn with the structure of Ce^IV(CrO₄)₂·2H₂O.     

On the Crystal Structure of K2Cu5Cl8(OH)4·2H2O

Single crystals of K₂Cu₅Cl₈(OH)₄·2H₂O were grown using hydrothermal techniques. The compound is monoclinic with a = 11.6424(11), b = 6.5639(4), c = 11.7710(10)Å, β = 91.09(1)°, V = 899.4(2)ų, space group P2₁/c, Z = 2. The crystal structure was determined using single crystal X‐ray diffraction data and refined to a residual of R(|F|) = 0.025 for 1208 independent observed reflections with I > 2σ(I). Two out of three crystallographically independent Cu atoms are coordinated to four near hydroxyl groups or chlorine atoms and two more distant Cl atoms, giving an octahedrally Jahn‐Teller distorted (4+2)‐configuration. For the remaining third copper cation a square‐planar coordination can be found. Edge‐sharing of the octahedra results in the formation of kagome‐type sheets parallel to (100). The octahedral layers are decorated on both sides by planar [Cu(OH)₂Cl₂]‐units around the third Cu atom. The K atoms are located between adjacent sheets and are surrounded by six Cl atoms as well as two water molecules. The coordination polyhedra about the K‐atoms can be described as distorted bicapped trigonal prisms. Additional linkage is provided by intra‐ as well as inter‐layer hydrogen bonds (O—H···Cl, O—H···O).     

Syntheses and Structures of Na2Mg3(OH)2(SO4)3·4H2O and K2Mg3(OH)2(SO4)3·2H2O

The crystal structures of Na₂Mg₃(OH)₂(SO₄)₃ · 4H₂O and K₂Mg₃(OH)₂(SO₄)₃ · 2H₂O, were determined from conventional laboratory X‐ray powder diffraction data. Synthesis and crystal growth were made by mixing alkali metal sulfate, magnesium sulfate hydrate, and magnesium oxide with small amounts of water followed by heating at 150 °C. The compounds crystallize in space group Cmc2₁ (No. 36) with lattice parameters of a = 19.7351(3), b = 7.2228(2), c = 10.0285(2) Å for the sodium and a = 17.9427(2), b = 7.5184(1), c = 9.7945(1) Å for the potassium sample. The crystal structure consists of a linked MgO₆–SO₄ layered network, where the space between the layers is filled with either potassium (K⁺) or Na⁺‐2H₂O units. The potassium‐bearing structure is isostructural to K₂Co₃(OH)₂(SO₄)₃ · 2(H₂O). The sodium compound has a similar crystal structure, where the bigger potassium ion is replaced by sodium ions and twice as many water molecules. Geometry optimization of the hydrogen positions were made with an empirical energy code.     

Earth Alkaline Tetrathiosquarates. II. – Syntheses and Crystal Structures of SrC4S4·4 H2O and Ba4K2(C4S4)5·16 H2O

Concentrated aqueous solutions of strontium chloride and barium chloride, respectively, allow on addition of the potassium salt of tetrathiosquarate, K₂C₄S₄·H₂O, the isolation of the earth alkaline salts SrC₄S₄·4 H₂O ( 1 ) and Ba₄K₂(C₄S₄)₅·16 H₂O ( 2 ), both as dark red crystals. The crystal structure determinations ( 1 : orthorhombic, Pnma, a = 8.149(1), b = 12.907(2), c = 10.790(2) Å, Z = 4; 2 : orthorhombic, Pbca, a = 15.875(3), b = 21.325(5), c = 16.119(1) Å, Z = 4) show the presence of C₄S₄²⁻ ions with only slightly distorted D_4h symmetry having average C–C and C–S bond lengths of 1.41Å and 1.681Å for 1 and 1.450Å and 1.657Å for 2 . The structure of 1 contains concatenated edge‐sharing Sr(H₂O)₆S₂ polyhedra. The Sr²⁺ ions are in eight‐fold coordination with Sr–O distances of 2.50–2.72Å and Sr–S distances of 3.21Å, (C₄S₄)²⁻ acts as a chelating ligand towards Sr²⁺. The structure is closely related to the previously reported Ca²⁺ containing analogue, which is of lower symmetry belonging to the monoclinic crystal system. A supergroup‐subgroup relation between the space groups of both structures is present. The structure of 2 is made up of Ba²⁺ and K⁺ ions in eight and nine‐fold coordination by H₂O molecules and (C₄S₄)²⁻ ions which act as chelating ligands towards one cation and bridging between two cations. The coordination polyhedra of the cations are connected by common edges and corners in two dimensions to layers which are connected by tetrathiosquarate ions to a three‐dimensional network. The infrared and Raman spectra show bands typical for the molecular building units of the two compounds.     

Preparation,Crystal Structure and Vibrational Spectra of Ca2P2O6·2H2O and [Ca(H2O)3(H2P2O6)]·0.5(C12H24O6)·H2O

The calcium salts Ca₂P₂O₆ · 2H₂O ( 1 ) and [Ca(H₂O)₃(H₂P₂O₆)] · 0.5(C₁₂H₂₄O₆) · H₂O ( 2 ) were prepared and structurally characterized by single‐crystal X‐ray diffraction. Compound 1 crystallizes in the orthorhombic space group Pbca and compound 2 in the monoclinic space group P2₁/n. The crystal structure of compound 1 consists of chains of edge‐sharing [CaO₇] polyhedra linked by hypodiphosphate(IV) anions to form a three‐dimensional network. The crystal structure of compound 2 consists of alternated layers of crown ether and water molecules and respective ionic units. Within the layers of ionic units the Ca²⁺ cations are octahedrally coordinated by three monodentate dihydrogenhypodiphosphate(IV) anions and three water molecules. The IR/Raman spectra of the title compounds were recorded and interpreted, especially with respect to the [P₂O₆]^4– and [H₂P₂O₆]^2– groups. The phase purity of 2 was verified by powder diffraction measurements.     

Synthesis,Crystal Structure and Magnetism of the New Oxysulfide Ce3NbO4S3

The orange cerium‐niobium‐oxysulfide Ce₃NbO₄S₃ was synthesized by the solid state reaction of CeO₂, Ce‐metal, Nb₂O₅ and sulfur at 1100 °C. The crystal structure has orthorhombic symmetry (space group Pbam, a = 7.055(1), b = 14.571(3), c = 7.627(2) Å, Z = 4) and contains isolated [Nb₂S₄O₆]¹⁰⁻ ions consisting of two strongly distorted, edge sharing NbO₃SS_2/2 octahedra. Niobium is connected to three oxygen and three sulfur atoms. The cerium atoms are eightfold coordinated by oxygen and sulfur atoms. Certain oxygen and sulfur atoms are not connected to niobium, but exclusively surrounded by cerium. By connecting these cation polyhedra, one recognizes layers of polycations perpendicular to the c‐axis. The magnetic susceptibility shows Curie‐Weiss behavior with an effective magnetic moment μ_eff = 2.63(1) μ_B/Ce in agreement with Ce³⁺. A Weiss‐constant θ_p = –12(1) K indicates weak antiferromagnetic coupling. No magnetic ordering was detected above 2 K.     

Cerous sodium nitrate monohydrate,Na2Ce(NO3)5·H2O

The title compound, disodium cerium pentanitrate monohydrate, was synthesized from a nitric acid solution of Ce(NO₃)₃·6H₂O and NaNO₃, and its structure has been determined from single‐crystal X‐ray diffraction data. The structure is built from isolated chains of irregular icosahedral [Ce(NO₃)₆]^3? anions. Na atoms and water mol­ecules are located between the chains. The Na coordination polyhedra, in the form of a square antiprism or a monocapped square antiprism, share common vertices and contribute to the formation of a three‐dimensional network. Ten nitrate groups act as bridging ligands.     

Einkristalle des Cer(III)‐Borosilicats Ce3[BSiO6][SiO4]

Single Crystals of the Cerium(III) Borosilicate Ce₃[BSiO₆][SiO₄] Colorless, lath‐shaped single crystals of Ce₃[BSiO₆]‐ [SiO₄] (orthorhombic, Pbca; a = 990.07(6), b = 720.36(4), c = 2329.2(2) pm, Z = 8) were obtained in attempts to synthesize fluoride borates with trivalent cerium in evacuated silica tubes by reaction of educt mixtures of elemental cerium, cerium dioxide, cerium trifluoride, and boron sesquioxide (Ce, CeO₂, CeF₃, B₂O₃; molar ratio 3 : 1 : 3 : 3) in fluxing CsCl (700 °C, 7 d) with the glass wall. The crystal structure contains eight‐ (Ce1) and ninefold coordinated Ce³⁺ cations (Ce2 and Ce3) surrounded by oxygen atoms. Charge balance is achieved by both discrete borosilicate ([BSiO₆]^5– ≡ [O₂BOSiO₃]^5–) and ortho‐silicate anions ([SiO₄]^4–). The former consists of a [BO₃] triangle linked to a [SiO₄] tetrahedron by a single vertex. The anions form layers in [001] direction alternatingly built up from [BSiO₆]^5– and [SiO₄]^4– groups while Ce³⁺ cations are located in between.     

Trivalent‐Intermediate Valent Cerium Ordering in Ce2RuZn4

The new intermetallic cerium compound Ce₂RuZn₄ was synthesized from the elements in a sealed tantalum tube in a water‐cooled sample chamber of an induction furnace. Ce₂RuZn₄ crystallizes with a new structure type: P4/nmm, Z = 2, a = 719.6(1), c = 520.2(1) pm, wR2 = 0.0816, 273 F² values and 15 variables. The structure contains two crystallographically independent cerium atoms: Ce1 with CN 16 (12 Zn + 4 Ce) and Ce2 with CN 14 (2 Ru + 8 Zn + 4 Ce). Based on the interatomic distances the two sites can be assigned to trivalent Ce1 and intermediate valent Ce2. The trivalent‐intermediate valent cerium ordering is underlined by magnetic susceptibility measurements. Ce₂RuZn₄ shows modified Curie‐Weiss behaviour in the temperature range 10–290 K with an experimental magnetic moment of 2.57(1) μ_B per formula unit. Thus only half of the cerium atoms are trivalent in Ce₂RuZn₄. A remarkable feature of the Ce₂RuZn₄ structure are short Ce2–Ru distances of 260 pm. The crystal chemistry of Ce₂RuZn₄ is discussed.     

Potassium cerium(III) bis­(sulfate) monohydrate,KCe(SO4)2·H2O

The crystal structure of potassium cerium(III) bis­(sulfate) monohydrate, KCe(SO₄)₂·H₂O, is built up from irregular independent SO₄ tetra­hedra, CeO₉ polyhedra in the form of distorted tricapped trigonal prisms and K⁺ ions. Hydrogen bonding between the free water mol­ecule and sulfate groups supplement the ionic bonds characteristic of the rest of the structure.     

Die Kristallstruktur von Trikobalt(II)-dihydroxidsulfat-dihydrat,Co3(OH)2(SO4)2 · 2 H2O

Tricobalt (II)-dihydroxidesulfate-dihydrate, Co₃(OH)₂(SO₄)₂ · 2H₂O, is orthorhombic: a = 7.21, b = 9.77, c = 12.86 Å, V = 905.9 ų, space group D-Pbcm with four formula units per cell. The atomic positions have been determined by threedimensional Patterson and Fourier synthesis and full-matrix least-squares refinement of single crystal X-ray diffraction data. The structure shows infinite chains [001] of Co? O octahedra sharing one edge with each other. These chains are linked together by alternating SO₄ tetrahedra and additional Co? O octahedra, thus giving rise to a three-dimensional network of polyhedra. There is no similarity to the well known layer structures of most hydroxide salts of divalent metals. The SO₄ tetrahedra are regular while the Co? O octahedra show considerable distortion. The water molecule is coordinated to one Co atom and bonded to sulfate oxygen by two weak hydrogen bridges.     

(NH4)3[VO2(SO4)2(H2O)2]·1.5H2O

The title compound, tri­ammonium cis‐di­aqua‐cis‐dioxo‐trans‐disulfatovanadate 1.5‐hydrate, was obtained by oxidizing V^IV to V^V in a 2 M sulfuric acid solution of vanadyl­ sulfate and adding ammonium sulfate. Here, the V atom is sandwiched by two sulfate groups by corner‐sharing to form a discrete [VO₂(SO₄)₂(OH₂)₂]^3? anion. The water mol­ecules occupy cis positions in the equatorial plane of the vanadium octahedron.     

Cerium triiodate,Ce(IO3)3

The crystal structure of Ce(IO₃)₃ consists of one‐dimensional chains of edge‐sharing CeO₉ polyhedra which are crosslinked into two‐dimensional layers through bridging IO₃⁻ groups. The layers are held together via long I⋯O contacts, resulting in an extended three‐dimensional network. The I—O bond distances and O—I—O angles are normal, lying in the ranges 1.806 (4)–1.846 (4) Å and 89.9 (2)–100.9 (2)°, respectively. The three crystallographically independent iodate groups all show different coordination modes.     

Synthesis,Structural Characterization and Thermal Stability of [Mn(3‐bpd)2(NCS)2(H2O)2]·2H2O (1) and {[Mn(bpe)(NCS)2(H2O)2]·(3‐bpd)·(bpe)·H2O}n (2) from One‐Pot Crystallization

Two supramolecular architectures, [Mn(3‐bpd)₂(NCS)₂(H₂O)₂]·2H₂O ( 1 ) and {[Mn(bpe)(NCS)₂(H₂O)₂]·(3‐bpd)·(bpe)·H₂O}_n ( 2 ) [bpe = 1,2‐bis(4‐pyridyl)ethylene and 3‐bpd = 1,4‐bis(3‐pyridyl)‐2,3‐diaza‐1,3‐butadiene] have been synthesized and characterized by spectroscopic, elemental and single crystal X‐ray diffraction analyses. Compound 1 crystallizes in the monoclinic system, space group P2₁/c, with chemical formula C₂₆H₂₈Mn N₁₀O₄S₂, a = 9.1360(6), b = 9.7490(6), c = 17.776(1) Å, β = 93.212(1)°, and Z = 2 while compound 2 crystallizes in the orthorhombic system, space group P2₁2₁2₁, with chemical formula C₃₈H₃₆Mn₁N₁₀O₃S₂, a = 14.1902(6), b = 15.4569(7), c = 18.2838(8) Å, α = β = γ = 90°, and Z = 4. Structural determination reveals that the coordination geometry at Mn(II) in compound 1 or 2 is a distorted octahedral which consists of two nitrogen donors of two NCS^?ligands, two oxygen donors of two water molecules, and two nitrogen donors of two 3‐bpd ligands for 1 and two dpe ligands for 2 , respectively. The two 3‐bpd ligands in 1 adopt a monodentate binding mode and the dpe in 2 adopts a bismonodentate bridging mode to connect the Mn(II) ions forming a 1D chain‐like coordination polymer. Both the π‐π stacking interactions between the coordinated and the free pyridyl‐based ligands and intermolecular hydrogen bonds among the coordinated and the crystallized water molecules and the free pyridyl‐based ligands play an important role in construction of these 3D supramolecular architectures.     

Synthesis and Characterization of the Synthetic Minerals Villyaellenite and Sarkinite,Mn5(AsO4)2(HAsO4)2 · 4H2O and Mn2(AsO4)(OH)

Using hydrothermal methods, two manganese arsenates have been synthesized and characterized by single crystal X‐ray diffraction. The products Mn₅(AsO₄)₂(HAsO₄)₂ ?4H₂O ( 1 ) and Mn₂AsO₄(OH) ( 2 ), the Mn end‐members of the minerals villyaellenite and sarkinite, respectively, have been obtained (crystal data 1 : monoclinic, C2/c, a = 18.109(4), b = 9.332(2), c = 9.809(2) Å, β = 96.172(4)?, Z = 4; 2 : monoclinic, P2₁/c, a = 10.219(2), b = 13.613(2), c = 12.780(2) Å, β = 108.834(2)?, Z = 16). In both compounds a three‐dimensional framework of edge‐sharing MnO polyhedra is observed. Based on the availability of the all Mn2containing form of villyaellenite ( 1 ), the ordering scheme of the impurity cations of the natural samples could be confirmed. Magnetic susceptibility measurements of 1 indicate the presence of high‐spin Mn²⁺ ions. The comparison of the data on sarkinite ( 2 ) with the data obtained from the natural sample indicates that the mineral has either a very high Mn content, or an absence of impurity cation ordering.     

Solvothermal Synthesis,Crystal Structure and Properties of a New Organic Templated Lanthanum Sulfate [C4N3H16][La(SO4)3(H2O)]

A new organic templated lanthanum sulfate [C₄N₃H₁₆][La(SO₄)₃(H₂O)] ( 1 ) has been solvothermally synthesized by using n‐butanol as solvent. The colorless block crystals were characterized by IR, TGA, ICP, and XRD. The structure was determined by single‐crystal X‐ray diffraction: Monoclinic, P2₁/c, a = 10.8878(19), b = 15.478(3), c = 9.9639(18) Å, β = 114.062(2)°, V=1533.2(5) ų, Z = 4]. Crystal structure analysis shows that the one dimensional chain of 1 consists of the LaO₉ polyhedra and the sulfate groups. Coordination water molecules link adjacent chains by using hydrogen bonds to generate 2D layers, whereas the organic amines are inserted between the layers. The formation of 1 demonstrates that solvents play an important role during the synthesis.     

[(C2H5)3NH]2Sn3Se7 · 0,25 H2O und [(C3H7)2NH2]4Sn4Se10 · 4 H2O

Synthesis, Structure, and Properties of Some Selenidostannates. II. [(C₂H₅)₃NH]₂Sn₃Se₇ · 0,25 H₂O and [(C₃H₇)₂NH₂]₄Sn₄Se₁₀ · 4 H₂O The new selenidostannate hydrates [(C₂H₅)₃NH]₂Sn₃Se₇ · 0.25 H₂O ( I ) and [(C₃H₇)₂NH₂]₄Sn₄Se₁₀ · 4 H₂O ( II ) were synthesized from an aqueous suspension of triethylammonium (tripropylammonium), tin, selenium I and in addition sulfur II at 130 °C. I crystallizes at ambient temperature in the monoclinic space group P2₁/n (a = 2069,3(4) pm, b = 1396,6(3) pm, c = 2342,8(5) pm, β = 114,68(3)°, Z = 8) and is characterized by two different anions, chains from edge‐sharing [Se₃Se₇]^2– units and nets from trigonal SnSe₅ bipyramids. II crystallizes at ambient temperature in the tetragonal space group I4₁/amd (a = 2150,0(3) pm, c = 1174,4(2) pm, Z = 4) and contains adamantane like [Sn₄Se₁₀]^4–‐cages. The UV‐VIS spectra of the selenidostannates demonstrate that the absorption edges red shift as the dimensionality of the compounds is increased.     

A uranyl sulfate cluster in Na10[(UO2)(SO4)4](SO4)2·3H2O

Decasodium uranyl hexa­sulfate trihydrate, Na₁₀[(UO₂)(SO₄)₄](SO₄)₂·3H₂O, contains an unusual uranyl sulfate cluster with the composition [(UO₂)(SO₄)₄]^6?. The cluster is composed of a uranyl pentagonal bipyramid and four sulfate tetrahedra. Three sulfate tetrahedra are linked to the uranyl pentagonal bipyramid by the sharing of vertices, and the other shares an equatorial edge of the uranyl pentagonal bipyramid. The uranyl sulfate clusters occur in layers parallel to (010). The structure also contains two isolated symmetrically distinct sulfate tetrahedra, which also occur in layers parallel to (010). The uranyl sulfate clusters and isolated sulfate tetrahedra are linked through bonds to Na⁺ cations, and by hydrogen bonding involving the water molecules.