KNi3(AsO4)(As2O7)

The structure of the title compound, potassium trinickel arsenate diarsenate, is built up from corner‐ and edge‐sharing NiO₆ octahedra, AsO₄ tetrahedra and As₂O₇ groups, giving rise to a polyhedral connectivity which produces large tunnels running along the crystallographic [010] direction. The K⁺ cations are located within these tunnels.     

Octa­hedral–tetra­hedral framework structures of InAsO4·H2O and PbIn(AsO4)(AsO3OH)

Indium arsenate(V) monohydrate, InAsO₄·H₂O, (I), crystallizes in the structure type of MnMoO₄·H₂O. The structure is built of In₂O₈(H₂O)₂ dimers (mean In—O = 2.150 Å) corner‐linked to slightly distorted AsO₄ tetra­hedra (mean As—O = 1.686 Å). The linkage results in a three‐dimensional framework, with small voids into which the apical water ligand of the InO₅(H₂O) octa­hedron points. The hydrogen bonds in (I) are of medium strength. Lead(II) indium arsenate(V) hydrogen arsenate(V), PbIn(AsO₄)(AsO₃OH), (II), represents the first reported lead indium arsenate. It is characterized by a framework structure of InO₆ octa­hedra corner‐linked to AsO₄ and AsO₃OH tetra­hedra. The resulting voids are occupied by Pb₂O₁₀(OH)₂ dimers built of two edge‐sharing highly distorted PbO₆(OH) polyhedra (mean Pb—O = 2.623 Å). The compound is isotypic with PbFe^III(AsO₄)(AsO₃OH). The average In—O bond length in (II) is 2.157 Å. In both arsenates, all atoms are in general positions.     

Single Crystal Growth and Crystal Structure of Mercurous Diarsenate(V), (Hg2)2(As2O7)

Polycrystalline mercurous diarsenate(V), (Hg₂)₂(As₂O₇), was prepared by a redox‐reaction between stoichiometric amounts of HgO and As₂O₃. Canary yellow single crystals were obtained by subsequent chemical transport reactions using HgCl₂ as transport agent [550 → 500 °C, 5 d, sealed and evacuated silica ampoules]. The crystal structure (orthorhombic, Pnma, Z = 4, a = 9.9803(8), b = 12.2039(10), c = 7.2374(6)Å) is composed of two crystallographically independent Hgequation/tex2gif-stack-1.gif dumbbells (d¯(Hg—Hg) = 2.5133Å) with a symmetric oxygen coordination sphere, and a diarsenate group with a staggered conformation and a bent bridging angle As—O—As = 121.0(7)°. The building units are arranged in a layer‐like assembly parallel to (010) and are connected via common oxygen atoms to form a three‐dimensional network.     

Three new acid M+ arsenates and phosphates with multiply protonated As/PO4 groups

The crystal structures of caesium dihydrogen arsenate(V) bis[trihydrogen arsenate(V)], Cs(H₂AsO₄)(H₃AsO₄)₂, ammonium dihydrogen arsenate(V) trihydrogen arsenate(V), NH₄(H₂AsO₄)(H₃AsO₄), and dilithium bis(dihydrogen phosphate), Li₂(H₂PO₄)₂, were solved from single‐crystal X‐ray diffraction data. NH₄(H₂AsO₄)(H₃AsO₄), which was hydrothermally synthesized (T = 493 K), is homeotypic with Rb(H₂AsO₄)(H₃AsO₄), while Cs(H₂AsO₄)(H₃AsO₄)₂ crystallizes in a novel structure type and Li₂(H₂PO₄)₂ represents a new polymorph of this composition. The Cs and Li compounds grew at room temperature from highly acidic aqueous solutions. Li₂(H₂PO₄)₂ forms a three‐dimensional (3D) framework of PO₄ tetrahedra sharing corners with Li₂O₆ dimers built of edge‐sharing LiO₄ groups, which is reinforced by hydrogen bonds. The two arsenate compounds are characterized by a 3D network of AsO₄ groups that are connected solely via multiple strong hydrogen bonds. A statistical evaluation of the As—O bond lengths in singly, doubly and triply protonated AsO₄ groups gave average values of 1.70 (2) Å for 199 As—OH bonds, 1.728 (19) Å for As—OH bonds in HAsO₄ groups, 1.714 (12) Å for As—OH bonds in H₂AsO₄ groups and 1.694 (16) Å for As—OH bonds in H₃AsO₄ groups, and a grand mean value of 1.667 (18) Å for As—O bonds to nonprotonated O atoms.     

Zur Kenntnis von Cr2H2(As2O7)(As4O12)

The crystal structure of Cr₂H₂(As₂O₇)(As₄O₁₂) has been determined by X-ray methods using single crystal diffractometer data (1,152 reflections,R=0.054, orthorhombic,Pmmn,a=1317.7 (7),b=1124.9 (6),c=494.3 (4) pm,Z=2). The crystal structure contains both diarsenate(V) and the hitherto unknown cyclo-tetraarsenate(V)-anions. The magnetic susceptibility follows theCurie-Weiss law (=3.86±0.01 _B/Cr³⁺, =–31 K).

     

CsGa(H1.5AsO4)2(H2AsO4) and isotypic CsCr(H1.5AsO4)2(H2AsO4): decorated kröhnkite‐like chains in two unusual hydrogen arsenates

Hydro­thermally synthesized caesium gallium(III) hydrogen arsenate(V), CsGa(H_1.5AsO₄)₂(H₂AsO₄), (I), and isotypic caesium chromium(III) hydrogen arsenate(V), CsCr(H_1.5AsO₄)₂(H₂AsO₄), (II), represent a new structure type and stoichiometry among M^I–M^III hydrogen arsenates. The crystal structure, determined from single‐crystal X‐ray diffraction data, is based on an infinite octa­hedral–tetra­hedral chain and can be described as a decorated kröhnkite‐like chain. The chains extend parallel to [100] and are separated by ten‐coordinated Cs atoms. The hydrogen‐bonding scheme comprises one very short symmetry‐restricted hydrogen bond, with O⋯O distances of 2.519 (4) and 2.508 (4) Å in (I) and (II), respectively, and two further medium–strong hydrogen bonds, all of which reinforce the connections between adjacent chains. The average Ga—O and Cr—O bond lengths are 1.973 (15) and 1.980 (13) Å, respectively, and the average As—O bond lengths in the two protonated arsenate groups lie within a very narrow range [1.690 (18)–1.69 (3) Å]. The Cs atom is located on a centre of inversion, while the M^III and As2 atoms lie on twofold axes. Relationships to CaBa₂(HPO₄)₂(H₂PO₄)₂ and other compounds containing decorated kröhnkite‐type or kröhnkite‐like chains are discussed.     

CsAl(H2AsO4)2(HAsO4): a new monoclinic protonated arsenate with decorated kröhnkite‐like chains

The crystal structure of hydro­thermally synthesized caesium aluminium bis­[dihydrogen arsenate(V)] hydrogen arsen­ate(V), CsAl(H₂AsO₄)₂(HAsO₄), was determined from single‐crystal X‐ray diffraction data collected at room temperature. The compound represents a new structure type that is characterized by decorated kröhnkite‐like [100] chains of corner‐sharing AlO₆ octa­hedra and AsO₄ tetra­hedra. Ten‐coordinated Cs atoms are situated between the chains, which are inter­connected by five different hydrogen bonds [O⋯O = 2.569 (4)–2.978 (4) Å]. All atoms are in general positions. CsAl(H₂AsO₄)₂(HAsO₄) is very closely related to CsGa(H_1.5AsO₄)₂(H₂AsO₄) and isotypic CsCr(H_1.5AsO₄)₂(H₂AsO₄).     

β‐LiMoO2(AsO4)

A new non‐centrosymmetrical form of lithium molybdyl arsenate has been synthesized and grown as a single crystal. The structure of β‐LiMoO₂(AsO₄) is built up of corner‐sharing AsO₄ tetrahedra and MoO₆ octahedra which form a three‐dimensional framework containing tunnels running along the a axis, wherein the Li⁺ cations are located. This novel structure is compared with the compound LiMoO₂(AsO₄) of the same formula, and with those of AMO₂(XO₄) (A is Na, K, Rb or Pb, M is Mo or V, and X is P or As) and B(MoO₂)₂(XO₄)₂ (B is Ba, Pb or Sr).     

AgCo3H2(AsO4)3 und AgZn3H2(AsO4)3 Darstellung und Kristallstruktur Ein weiterer neuer Arsenat-Strukturtyp

AgCo₃H₂(AsO₄)₃ and AgZn₃H₂(AsO₄)₃. Preparation and Crystal Structure. Another New Structure Type of an Arsenate AgCo₃H₂(AsO₄)₃ ( 1 ) and AgZn₃H₂(AsO₄)₃ ( 2 ) were prepared by heating of As₂O₅, AgNO₃, CoSO₄ · 7H₂O, ZnSO₄ · 7H₂O, respectively, and water in a sealed tube at 300°C and investigated with X-rays. Both compounds are isotypic and crystallize in the monoclinic space group C2/c with 4 formula units per cell. The lattice parameters are ( 1 ): a = 1215.9(6), b = 1243.8(7), c = 678.2(3) pm, β = 113.16(3)° ( 2 ): a = 1216.9(2), b = 1249.5(3), c = 675.5(1) pm, β = 112.77(1)°. The structure contains chains of edge-shared CoO₆ or ZnO₆ octahedra, respectively, which are connected by AsO₄ tetrahedra and silver oxygen ribbons with square planar coordinated silver forming a framework. Based on the charge balances derived from the geometrical data and the IR spectra the occurence of hydrogen bonds is discussed.     

Two New Polyoxovanadate‐supported Transition Metal Complexes: [Zn(en)2][Zn(en)2(H2O)2][{Zn(en)(enMe)}As6V15O42(H2O)]·4H2O and [Zn2(enMe)2(en)3][{Zn(enMe)2}As6V15O42(H2O)]·4H2O

Two novel As‐V‐O cluster supported transition metal complexes, [Zn(en)₂][Zn(en)₂(H₂O)₂][{Zn(en)(enMe)}As₆V₁₅O₄₂(H₂O)]·4H₂O ( 1 ) and [Zn₂(enMe)₂(en)₃][{Zn(enMe)₂}As₆V₁₅O₄₂(H₂O)]·4H₂O ( 2 ), have been hydrothermally synthesized. The single X‐ray diffraction studies reveal that both compounds consist of discrete noncentral polyoxoanions [{Zn(en)(enMe)}As₆V₁₅O₄₂(H₂O)]^4? or [{Zn(enMe)₂}As₆V₁₅O₄₂(H₂O)]^4? cocrystallized with respective zinc coordination complexes. Interestingly, compounds 1 and 2 exhibit the first two polyoxovanadates containing As₈V₁₅O₄₂‐(H₂O)]^6? cluster decorated by only one transition metal complex. Crystal data: 1 , monoclinic, P2₁/n, a = 14.9037(4) Å, b = 18.1243(5) Å, c = 27.6103(7) Å, β = 105.376(6)°, Z = 4; 2 monoclinic, P2₁/n, a = 14.9786(7) Å, b = 33.0534(16) Å, c = 14.9811(5) Å, Z = 4.     

M+M3+2As(HAsO4)6 and α‐ and β‐M+M3+(HAsO4)2 (M+M3+ = RbAl or CsFe): six new compounds crystallizing in three closely related structure types

The crystal structures of hydrothermally synthesized (T = 493 K, 7–9 d) rubidium aluminium bis[hydrogen arsenate(V)], RbAl(HAsO₄)₂, caesium iron bis[hydrogen arsenate(V)], CsFe(HAsO₄)₂, rubidium dialuminium arsenic(V) hexakis[hydrogen arsenate(V)], RbAl₂As(HAsO₄)₆, and caesium diiron arsenic(V) hexakis[hydrogen arsenate(V)], CsFe₂As(HAsO₄)₆, were solved by single‐crystal X‐ray diffraction. The four compounds with the general formula M⁺M³⁺(HAsO₄)₂ adopt the RbFe(HPO₄)₂ structure type (Rc) and a closely related new structure type, which is characterized by a different stacking order of the building units, leading to noncentrosymmetric space‐group symmetry R32. The second new structure type, with the general formula M⁺M³⁺₂As(HAsO₄)₆ (Rc), is also a modification of the RbFe(HPO₄)₂ structure type, in which one third of the M³⁺O₆ octahedra are replaced by AsO₆ octahedra, and two thirds of the voids in the structure, which are usually filled by M⁺ cations, remain empty to achieve charge balance.     

Crystal structure and proton conductivity of a new Cs3(H2PO4)(HPO4)·2H2O phase in the caesium di‐ and monohydrogen orthophosphate system

The M_x H_y (A O₄)_z acid salts (M = Cs, Rb, K, Na, Li, NH₄; A = S, Se, As, P) exhibit ferroelectric properties. The solid acids have low conductivity values and are of interest with regard to their thermal properties and proton conductivity. The crystal structure of caesium dihydrogen orthophosphate monohydrogen orthophosphate dihydrate, Cs₃(H_1.5PO₄)₂·2H₂O, has been solved. The compound crystallizes in the space group Pbca and forms a structure with strong hydrogen bonds connecting phosphate tetrahedra that agrees well with the IR spectra. The dehydration of Cs₃(H_1.5PO₄)₂·2H₂O with the loss of two water molecules occurs at 348–433 K. Anhydrous Cs₃(H_1.5PO₄)₂ is stable up to 548 K and is then converted completely into caesium pyrophosphate (Cs₄P₂O₇) and CsPO₃. Anhydrous Cs₃(H_1.5PO₄)₂ crystallizes in the monoclinic C 2 space group, with the unit‐cell parameters a = 11.1693 (4), b = 6.4682 (2), c = 7.7442 (3) Å and β = 71.822 (2)°. The conductivities of both compounds have been measured. In contrast to crystal hydrate Cs₃(H_1.5PO₄)₂·2H₂O, the dehydrated form has rather low conductivity values of ∼6 × 10⁻⁶–10⁻⁸ S cm⁻¹ at 373–493 K, with an activation energy of 0.91 eV.     

Sm2As4O9: Ein ungewöhnliches Samarium(III)‐Oxoarsenat(III) gemäß Sm4[As2O5]2[As4O8]

Sm₂As₄O₉: An Unusual Samarium(III) Oxoarsenate(III) According to Sm₄[As₂O₅]₂[As₄O₈] Pale yellow single crystals of the new samarium(III) oxoarsenate(III) with the composition Sm₄As₈O₁₈ were obtained by a typical solid‐state reaction between Sm₂O₃ and As₂O₃ using CsCl and SmCl₃ as fluxing agents. The compound crystallizes in the triclinic crystal system with the space group (No. 2, Z = 2; a = 681.12(5), b = 757.59(6), c = 953.97(8) pm, α = 96.623(7), β = 103.751(7), γ = 104.400(7)°). The crystal structure of samarium(III) oxoarsenate(III) with the formula type Sm₄[As₂O₅]₂[As₄O₈] (≡ 2 × Sm₂As₄O₉) contains two crystallographically different Sm³⁺ cations, where (Sm1)³⁺ is coordinated by eight, but (Sm2)³⁺ by nine oxygen atoms. Two different discrete oxoarsenate(III) anions are present in the crystal structure, namely [As₂O₅]^4? and [As₄O₈]^4?. The [As₂O₅]^4? anion is built up of two Ψ¹‐tetrahedra [AsO₃]^3? with a common corner, whereas the [As₄O₈]^4? anion consists of four Ψ¹‐tetrahedra with ring‐shaped vertex‐connected [AsO₃]^3? pyramids. Thus at all four crystallographically different As³⁺ cations stereochemically active non‐binding electron pairs (“lone pairs”) are observed. These “lone pairs” direct towards the center of empty channels running parallel to [010] in the overall structure, where these “empty channels” being formed by the linkage of layers with the ecliptically conformed [As₂O₅]^4? anions and the stair‐like shaped [As₄O₈]^4? rings via common oxygen atoms (O1 – O6, O8 and O9). The oxygen‐atom type O7, however, belongs only to the cyclo‐[As₄O₈]^4? unit as one of the two different corner‐sharing oxygen atoms.     

V2O2F4(H2O)2·H2O: a new V4+ layer structure related to VOF3

V^IV oxyfluorides are of interest as frustrated magnets. The successful synthesis of two‐dimensionally connected vanadium(IV) oxyfluoride structures generally requires the use of ionic liquids as solvents. During solvothermal synthesis experiments aimed at producing two‐ and three‐dimensional vanadium(IV) selenites with triangular lattices, the title compound, diaquatetra‐μ‐fluorido‐dioxidodivanadium(IV) monohydrate, V₂O₂F₄(H₂O)₂·H₂O, was discovered and features a new infinite V⁴⁺‐containing two‐dimensional layer comprised of fluorine‐bridged corner‐ and edge‐sharing VOF₄(H₂O) octahedral building units. The synthesis was carried out under solvothermal conditions. The V⁴⁺ centre exhibits a typical off‐centring, with a short V=O bond and an elongated trans‐V—F bond. Hydrogen‐bonded water molecules occur between the layers. The structure is related to previously reported vanadium oxyfluoride structures, in particular, the same layer topology is seen in VOF₃.     

The Triclinic Lanthanoid(III) Halide Oxidoarsenates(III) Sm3Cl2[As2O5][AsO3] and Tm3Br2[As2O5][AsO3]

Pale yellow single crystals of the composition Ln₃X₂[As₂O₅][AsO₃] (Ln = Tm for X = Br and Ln = Sm for X = Cl) were obtained via solid-state reactions in the systems Ln₂O₃/As₂O₃ from sealed silica ampoules using different halides as fluxing agents. Sm₃Cl₂[As₂O₅][AsO₃] and Tm₃Br₂[As₂O₅][AsO₃] crystallize isotypically in the triclinic space group P1 with Z = 2 and cell parameters of a = 543.51(4) pm, b = 837.24(6) pm, c = 1113.45(8) pm, α = 90.084(2)°, β = 94.532(2)°, γ = 90.487(2)° for the samarium and a = 534.96(4) pm, b = 869.26(6) pm, c = 1081.84(8) pm, α = 90.723(2)°, β = 94.792(2)° γ = 90.119(2)° for the thulium compound. The isotypic crystal structure of both representatives exhibits three crystallographically different Ln³⁺ cations, each with a coordination number of eight. (Ln1)³⁺ and (Ln2)³⁺ are only coordinated by three oxygen atoms, whereas (Ln3)³⁺ shows additional contacts to halide anions in forming square [LnO₄X₄]^9– antiprisms. All As³⁺ cations are surrounded by three oxygen atoms in the shape of isolated [AsO₃]^3– ψ¹-tetrahedra. They occur either isolated or condensed as pyroanionic [As₂O₅]^4– units with a bridging oxygen atom. In both anions, non-binding lone-pair electrons are present at the As³⁺ cations with a pronounced stereochemically active function.     

Zur Kenntnis von Kaliumarseniten im Dreistoffsystem K2O?As2O3?H2O. Darstellung und Kristallstruktur von K3(HAs2O4)(As2O4) · 3/2 H2O

Concerning Potassium Arsenites in the Three-Component System K₂O? As₂O₃? H₂O. Preparation and Crystal Structure of K₃(HAs₂O₄) (As₂O₄) · 3/2 H₂O The phase K₃(HAs₂O₄)(As₂O₄) · 3/2 H₂O has been identified in the system K₂O? As₂O₃? H₂O at 40°C and characterized by X-ray structural analysis. In the crystal lattice independent polymetaarsenite anions, [HAs₂O₄^?]_n and [As₂O₄^2?]_n, adopt parallel zweier single chains.     

The isotypic hydrogen phosphate and arsenate dihydrates M2HXO4·2H2O (M = Rb,Cs; X = P,As)

The four isotypic alkaline metal monohydrogen arsenate(V) and phosphate(V) dihydrates M₂HXO₄·2H₂O (M = Rb, Cs; X = P, As) [namely dicaesium monohydrogen arsenate(V) dihydrate, Cs₂HAsO₄·2H₂O, dicaesium monohydrogen phosphate(V) dihydrate, Cs₂HPO₄·2H₂O, dirubidium monohydrogen arsenate(V) dihydrate, Rb₂HAsO₄·2H₂O, and dirubidium monohydrogen phosphate(V) dihydrate, Rb₂HPO₄·2H₂O] were synthesized by reaction of an aqueous H₃XO₄ solution with one equivalent of aqueous M₂CO₃. Their crystal structures are made up of undulating chains extending along [001] of tetrahedral [XO₃(OH)]⁻ anions connected via strong O—H...O hydrogen bonds. These chains are in turn connected into a three‐dimensional network via medium‐strength hydrogen bonding involving the water molecules. Two crystallographically different M⁺ cations are located in channels running along [001] or in the free space of the [XO₃(OH)]⁻ chains, respectively. They are coordinated by eight and twelve O atoms forming irregular polyhedra. The structures possess pseudosymmetry. Due to the ordering of the protons in the [XO₃(OH)]⁻ chains in the actual structures, the symmetry is reduced from C2/c to P2₁/c. Nevertheless, the deviation from C2/c symmetry is minute.     

Mg7(AsO4)2(HAsO4)4: a new magnesium arsenate with a very strong hydrogen bond

A new compound, heptamagnesium bis­(arsenate) tetrakis(hydrogenarsenate), Mg₇(AsO₄)₂(HAsO₄)₄, was synthesized by a hydro­thermal method. The structure is based on a three‐dimensional framework of edge‐ and corner‐sharing MgO₆, MgO₄(OH)₂, MgO₅, AsO₃(OH) and AsO₄ polyhedra. Average Mg—O and As—O bond lengths are in the ranges 2.056–2.154 and 1.680–1.688 Å, respectively. Each of the two non‐equivalent OH groups is bonded to both an Mg and an As atom. One OH group is involved in a very short hydrogen bond [O⋯O = 2.468 (3) Å]. The formula unit is centrosymmetric, with all atoms in general positions except for one Mg atom, which has site symmetry . The compound is isotypic with Mn₇(AsO₄)₂(HAsO₄)₄ and M₇(PO₄)₂(HPO₄)₄, where M is Fe, Co or Mn.     

Two Modifications of (TeO)(HAsO4) and its Dehydration Product (Te3O3)(AsO4)2 – Three more Examples of Tellurium(IV) with a Fivefold Oxygen Coordination

Two modifications of (TeO)(HAsO₄) were obtained by reacting tellurium dioxide with arsenic acid under boiling conditions (modification I, acid concentration 80 wt‐%) or under hydrothermal conditions (modification II, acid concentration 50 wt‐%). The crystal structures of the two modifications were determined from single‐crystal X‐ray data [modification I: P2₁/c, Z = 4, a = 7.4076(10), b = 5.9596(7), c = 9.5523(11) Å, β = 102.589(8)°, 2893 structure factors, 68 parameters, R[F² > 2σ(F²)] = 0.0247, wR₂(F² all) = 0.0530; modification II: P2₁/c, Z = 4, a = 6.2962(4), b = 4.7041(3), c = 13.9446(8) Å, β = 94.528(3)°, 2549 structure factors, 69 parameters, R[F² > 2σ(F²)] = 0.0207, wR₂(F² all) = 0.0462)]. Dehydration of (TeO)(HAsO₄)‐II at temperatures above 260 °C results in the formation of polycrystalline (Te₃O₃)(AsO₄)₂. Single crystals of the anhydrous product were grown either by heating stoichiometric amounts of the binary oxides TeO₂ and As₂O₅ in closed silica glass ampoules or with higher concentrated arsenic acid (80 wt‐%) under hydrothermal conditions at 220 °C. The common features in the crystal structures of (Te₃O₃)(AsO₄)₂ [P$\bar{1}$ , Z = 4, a = 6.5548(4), b = 7.6281(6), c = 15.0464(15) Å, α = 140.212(6), β = 102.418(9)°, γ = 77.346(5)°, 5718 structure factors, 146 parameters, R[F² > 2σ(F²)] = 0.0351, wR₂(F² all) = 0. 1093] and in that of the two modifications of acidic (TeO)(HAsO₄) are [TeO₅] square‐pyramids and [AsO₄] tetrahedra. In anhydrous (Te₃O₃)(AsO₄)₂ and in (TeO)(HAsO₄)‐II, a layered arrangement of the building units is found, whereas in the (TeO)(HAsO₄)‐I structure strands are formed. Different hydrogen bonding interactions are present in the two modifications of (TeO)(HAsO₄).     

Three New Thioantimonates(V): Solvothermal Syntheses and Crystal Structures of [M(chxn)3]3(SbS4)2·4H2O (M = Ni,Co) and [Co(dien)2][Co(tren)SbS4]2·4H2O

The three new thioantimonates(V) [Ni(chxn)₃]₃(SbS₄)₂·4H₂O ( I ), [Co(chxn)₃]₃(SbS₄)₂·4H₂O ( II ) (chxn is trans‐1,2‐diaminocyclohexane) and [Co(dien)₂][Co(tren)SbS₄]₂·4H₂O ( III ) (dien is diethylenetriamine and tren is tris(2‐aminoethyl)amine) were synthesized under solvothermal conditions. Compounds I and II are isostructural crystallizing in space group C2/c. The structures are composed of isolated [M(chxn)₃]²⁺ complexes (M = Ni, Co), [SbS₄]^3? anions and crystal water molecules. Short S···N/S···O/O···O separations indicate hydrogen bonding interactions between the different constituents. Compound III crystallizes in space group and is composed of [Co(dien)₂]²⁺ and [Co(tren)SbS₄]^? anions and crystal water molecules. In the cationic complex the Co²⁺ ion is in an octahedral environment of two dien ligands whereas in [Co(tren)SbS₄]^? the Co²⁺ ion is in a trigonal bipyramidal coordination of four N atoms of tren and one S atom of the [SbS₄]^3? anion, i.e., two different coordination polyhedra around Co²⁺ coexist in this compound. Like in the former compounds an extended hydrogen bonding network connects the complexes and the water molecules into a three‐dimensional network.