On the relationship between the structures of CuII complexes and their chemical transformations

The thermal decomposition of the complexes M ₂ ^I Cu(SO₄)₂ · 6 H₂O and M₂Ni(SO₄)₂ · · 6 H₂O (M^I=NH₄, K, Rb, Tl) containing the complex cation M^II(H₂O)₆ ²+ (M^Il = =Cu, Ni) was studied. The values of the experimental activation energyE obtained for the dehydration reactions of both complex cations were found to be influenced in different ways by the outer-sphere cations present. It was therefore concluded that the activation energy of the decomposition of Cu(H₂O)₆ ²⁺ depends on the degree of tetragonal distortion of this cation, which increases with the ionic radius of cation M^I. TheΔH values of the studied reactions depend less on the structures of the coordination polyhedra.     

The relationship between the structures of Cu(II) complexes and their chemical transformations

The thermal dehydration of the compounds M ₂ ^I [M^II(H₂O)₆](SeO₄)₂, where M^I=NH₄, K, Rb, Cs and Tl, and M=Cu and Ni, was studied in order to correlate the course of the decomposition with the known crystal structures. It was found that the stoichiometry of the reactions is the same as that established for the analogous sulphato compounds of Cu(II) and Ni(II), respectively. Because of the discrepancies between the room-temperature crystal structures and the observed decomposition stoichiometries, high-temperature powder diffractograms were taken. These indicated structural changes of the copper(II) compounds during heating. The powder patterns for different structure changes were calculated and compared with the experimental ones. It was shown that during the heating two axial CuH₂O bonds are shortened and two equatorial bonds are lengthened. The observed decomposition stoichiometry is compatible with the formation of four nearly equal Cu-H₂O bonds. The activation energies (E^*) and pre-exponential factors (log A) for the first dehydration reaction of the Cu(II) compounds display the following sequence of M^I: Tl > Rb > NH₄ > K, and they are the higher, the shorter the split equatorial Cu(II) bonds. For the compounds of Ni(II) the sequence of E^* and log A values is K > Tl > NH₄ > Rb > Cs.

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Zusammenfassung Zur Aufklärung des Zusammenhanges zwischen dem Zersetzungsweg und der bekannten Kristallstruktur wurde die thermische Dehydration der Verbindungen M ₂ ^I [M^II(H₂O)₆](SeO₄)₂ mit M^I=NH₄, K, Rb, Cs and Tl sowie mit m^II=Cu und Ni untersucht. Man fand für diese Reaktion die gleiche Stöchiometrie wie für die analogen Sulfatverbindungen von Cu(II) bzw. Ni(II). Wegen des Widerspruches zwischen der Kristallstruktur bei Raumtemperatur und der festgestellten Stöchiometrie der Zersetzungsreaktion wurden auch Pulverdiffraktionsaufnahmen bei höheren Temperaturen angefertigt. Bei Cu(II)-Verbindungen konnte während des Erhitzens eine Strukturänderung festgestellt werden. Für verschiedene Strukturänderungen wurden Pulveraufnahmen berechnet und mit den experimentellen verglichen. Es konnte gezeigt werden, da sich während des Erhitzens zwei axiale Cu-H₂O-Bindungen verkürzen und zwei äquatoriale Bindungen strecken. Die beobachtete Zersetzungsstöchiometrie entspricht der Bildung von vier anänhernd gleichen Cu-H₂O-Bindungen. Die Aktivierrungsenergie (E^*) und der präexponentielle Faktor (log A) und der ersten Dehydratationsreaktion der Cu(II)-Verbindungen sinken in folgender Reihenfolge für M^I:Tl, Rb, NH₄, K und sind umso größer, je kürzer die gespaltenen äquatorialen Cu(II)-Bindungen sind. Für Ni(II)-Verbindungen nehmen E^* und log A in folgenden Reichenfolge ab: K, Tl, NH₄, Rb, Cs.

     

The kinetics of olation of some hydroxoaquotetrammine-cobalt(III) complexes in the solid state

The solid-state kinetics for the olation reactions of [Co(NH₃₄(OH)(H₂O)]X₂ (where X  Cl^?, Br^?, or $\text{1}\text{2}$SO^2?₄ were determined by several different methods using dynamic and isothermal thermogravimetric data. For the reduced-time plot method, E values were 20, 43, and 25 kcal mol^?1 for the chloride-bromide, and sulfate complexes, respectively. For the Jacobs and Kureishy method, E values of 21, 37, and 17 kcal mol^?1, were obtained for the above three complexes, respectively. A possible reaction pathway is suggested for the olation reaction.     

Possible tests for the mechanisms of ligand exchange in solids: The deaquation-anation of [Cr(NH3)5(H2O)]X3 salts

The possibility of using correlations of ΔH⁺ and ΔH, and of ΔH⁺ and ΔS⁺ to gain insight into the mechanisms of ligand-exchange reactions in solids are discussed. These correlations are tested using literature values for the deaquation-anation reactions of [Cr(NH₃)₅(H₂O)]X₃, where X^? = Cl^?, Br^?, I^? or NO^?₃. The poor agreement in the activation parameters reported in the literature precluded a meaningful test of the ΔH?ΔH^* correlation. This poor agreement suggests that these activation parameters are strongly influenced by experimental factors that have not been controlled in studies to date. nevertheless, there is a linear correlation of ΔH² and ΔS² which gives an isokinetic temperature of 367 ± 11 K. This isokinetic behavior suggests that the same mechanism is operative throughout the series.     

Synthesis, structure, and photoluminescence properties of a novel 3D 3d-4f heterometallic polymer: Pr4(H2O)9Cu3.5Cl0.5(Bpdc)6.5(OH)2 · 5H2O (H2Bpdc = 2,2′-bipyridyl-5,5-dicarboxylic acid)

A novel 3D 3d–4f heterometallic polymer Pr₄(H₂O)₉Cu_3.5Cl_0.5(Bpdc)_6.5(OH)₂ · 5H₂O (I) (H₂Bpdc = 2,2′-bipyridyl-5,5′-dicarboxylic acid) has been hydrothermally synthesized by the reaction of CuCl₂ · 2H₂O, PrCl₃, H₂Bpdc, TAA (TAA = 1H-tetrazolyl-1-acetic acid) and glacial acetic acid and characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction. Single-crystal structural analysis shows that I displays an interesting heterometallic 3D coordination framework constructed from 2D praseodymium-oxygen layers and [Cu(Bpdc)2]^3? and [CuCl(Bpdc)]^2? pillars. The photofluorescence properties of I have been investigated.     

Thermal decomposition of Cu(II) complexes with salicylaldehyde S-methyl thiosemicarbazone

The thermal decomposition of copper(II) complexes with salicylaldehyde S-methylthiosemicarbazone of general formula Cu(HL)X·nH₂O (X=Py+NO₃, NCS, 0.5SO₄) and [Cu(L)NH₃]·H₂O was investigated in air atmosphere in the interval from room temperature to 1000°C. Decomposition of the complexes occurred in several successive endothermic and exothermic processes, and the residue was in all cases CuO.     

Mono- and bi-metallic complexes based on redox-active tris(3,5-dimethylpyrazolyl)borato-molybdenum nitrosyls,part III.(1) Complexes containing meta-substituted benzene- and naphthalenediols or -diamines

Summary The complexes [MoL^*(NO)Cl(YC₆H₄YH-m)] (Y = O or NH), [MoL^*(NO)Cl(YC₁₀H₆YH-1,5)], (Y = O or NH), [MoL^*(NO)Cl(OC₁₀H₆OH-2,7)], [{MoL^*(NO)Cl}₂(XC₆H₄Y-m)] (X=Y=O, NH or S; X=O, Y=NH), [{MoL^*(NO)-C1}₂(YC₁₀H₆Y-1,5)] (Y=O or NH) and [{MoL^*(NO)Cl₂-(OC₁₀H₆-2,7)] have been prepared and studied by cyclic voltammetry. The monometallic species undergo a reversible oneelectron reduction, whereas the bimetallics undergo two oneelectron reductions. A comparison of E_1/2 (E_1/2(1)-E_1/2(2)) values for those new species with those obtained frompara- substituted analogues and bimetallics containing extended bridges YC₆H₄ZC₆H₄Y (e.g. Z = S or CH₂CH₂) established that the interaction between the redox centres in these new species is intermediate (YC₆H₄Y-m; NHC₁₀H₆NH-1,5) or weak (OC₁₀H₆O).In earlier papers^1,2 we have described the synthesis and electrochemical properties of a series of mono- and bi-metallic complexes of the type [MoL^*(NO)X(YC₆H₄YH)], [MoL^*(NO)X}₂(YC₆H₄Y)] and [{MoL^*(NO)X}₂(YC₆H₄-ZC₆H₄Y)] [L^*=tris(3,5-dimethylpyrazolyl)borate, HB(Me₂C₃HN₂)₃] where the arene ring ispara-substituted (X=Cl or I while Y=O, S or NH and Z = nothing, CH₂, CH₂CH₂, S, SO₂ or O). We have shown that the E_1/2-values of these species are dependent on X and Y, and that the bimetallic species undergo two one-electron reduction processes.We have established that there is strong interaction between the redox centres in bimetallics bridged byp-YC₆H₄Y, but that weak-to-negligible interaction occurs in those species containing YC₆H₄ZC₆H₄Y bridges. In this paper we describe our investigations ofmete-substituted bridging systems,m-YC₆H₄Y, and comparable systems containing naphthalene bridges,e.g. 1,5- or 2,7-YC₁₀H₂Y. From these studies we hoped to establish the extent of interaction between the two redox centres and how this compared to thepara-substituted arene counterparts.     

Solid chemistry of the Zn/1,2,4-triazolate/anion system: Separation of 2D isoreticular layers tuned by the terminal counteranions X (X=Cl, Br, I, SCN)

An array of 2D isoreticular layers, viz. [Zn(atrz)X]_∞ (1·X; X=Cl⁻, Br⁻, I⁻; atrz=3-amino-1,2,4-triazole anion), [Zn₄(atrz)₄(SCN)₄·H₂O]_∞ (1·SCN·H₂O) and [Zn(trz)X]_∞ (2·X; X=Cl⁻, Br⁻, I⁻; trz=1,2,4-triazole anion), have been hydrothermally synthesized and structurally characterized. Compounds 1·X and 1·SCN·H₂O are constructed from binuclear planar Zn₂(atrz)₂ subunits and exhibit (4,4) topological network when the subunits are simplified as four-connected nodes. Based on changing the terminal counteranions X (X=Cl⁻, Br⁻, I⁻, SCN⁻), the average interlayer separations of 1·X and 1·SCN·H₂O are enlarged, which equal to 5.851, 6.153, 6.651 and 8.292 Å, respectively. As a result, H₂O molecules reside in the spaces between two adjacent layers of 1·SCN·H₂O. 2 and 1 are the isomorphous structures. In common with 1, the interlayer separations of 2·X are widened with increasing the ion radius. Solid-state luminescence properties and thermogravimetric analyses of 1 and 2 were investigated, respectively.     

Mononuclear rearrangement of heterocycles in ionic liquids catalyzed by copper(II) salts

The reactivity of E- and Z-phenylhydrazones of 3-benzoyl-5-phenyl-1,2,4-oxadiazole in the presence of CuCl₂ and Cu(ClO₄)₂·6H₂O has been studied in four imidazolium ionic liquids [bmim][X] (X=BF₄⁻, PF₆⁻, SbF₆⁻ and CF₃SO₃⁻). The reaction may follow different mechanistic patterns, depending on the nature of the ionic liquid anion, accounting for both qualitative and kinetic data. In the presence of CuCl₂, two processes take place at the same time, i.e., the E?Z isomerization and the rearrangement of Z-isomer into the relevant 4-benzoylamino-2,5-diphenyl-1,2,3-triazole. In contrast, in the presence of Cu(ClO₄)₂·6H₂O, the rearrangement occurs only in solution of [bmim][BF₄] and [bmim][CF₃SO₃]. Collected data show that the effect of the ionic liquid on the isomerization and the rearrangement is different. In particular, a higher cross-linking degree seems to favour the triazole, but disfavour the E?Z isomerization.     

Structural and spectroscopic investigations of the Eu–CDTA system

Two crystal structures of Eu^III complexes with CDTA (trans-1,2-diaminocyclohexane-N,N,N′,N′-tetraacetate), [C(NH₂)₃]₃[Eu₂(CDTA)₂(H₂O)₂]ClO₄ · 7H₂O (I) and [C(NH₂)₃][Eu(CDTA)(H₂O)] · 2.375H₂O (II), are presented. Both structures are polymeric and the central metal ions are eight-coordinate. The first coordination sphere of each Eu^III cation contains five carboxylate oxygen atoms, two nitrogen ones and a water molecule. For I, as well as for water solutions of the Eu^III–CDTA complex at various pH values, the spectroscopic (UV–Vis) properties were investigated.     

Self-assembly hydrogen-bonded supramolecular arrays from copper(II) halogenobenzoates with nicotinamide: Structure and EPR spectra

Nicotinamide was employed as a supramolecular reagent in the synthesis of six new copper(II) bromo-, iodo-, fluoro- and dibromobenzoate complexes. Structures of [Cu(2-Brbz)₂(nia)₂(H₂O)₂] (I), [Cu(2-Ibz)₂(nia)₂(H₂O)2] (II), [Cu(2-Fbz)₂(nia)₂(H₂O)₂] (III), [Cu(4-Brbz)₂(nia)₂(H₂O)₂] (IV), [Cu(3,5-Br₂bz)2(nia)₂(H₂O)2] (V), [Cu(F-Fbz)₂(nia)₂(H₂O)] · H₂O (VI) (nia = nicotinamide, 2-Brbz = 2-bromobenzoate, 4-Brbz = 4-bromobenzoate, 3,5-Br₂bz = 3,5-dibromobenzoate, 2-Ibz = 2-iodobenzoate, 2-Fbz = 2-fluorobenzoate, 4-Fbz = 4-fluorobenzoate) were determined using X-ray analysis. Compound [Cu(2-Brbz)₂(nia)₂] · 2H₂O (VII) was prepared by a new method and also characterized by X-ray powder diffraction and EPR spectroscopy. Compounds I–V are monomeric complexes with a square-bipyramidal coordination sphere around the Cu²⁺ ion. Complex VI is monomeric with coordination environment around the Cu²⁺ ion of a tetragonal-pyramid. Complexes I and VII present examples of coordination isomerism. Molecules of all compounds are connected by N—H?O and O—H?O hydrogen bonds from the NH₂ groups of nicotinamide and water molecules which create supramolecular hydrogen-bonding-coordination chains and networks.     

Complexation in the CuCl2-C2H5OH-H2O system

Depending on the ethanol-water ratio, five individual compounds of copper(II) of the following compositions are formed in the CuCl₂-C₂H₅OH-H₂O system: [CuCl₂(C₂H₅OH)_4] (I), cis-[CuCl₂(C₂H₅OH)₂·(H₂O)₂] (II), trans-[CuCl₂(C₂H₅OH)₂· (H₂O)₂](III), [Cu(H₂O)₆]²⁺ (IV), and [Cu(OH)₂(H₂O)₄] (V).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2725–2729, December, 1990.     

Thermochemical investigations of the systems KCl−KBr−H2O,K2SO4−(NH4)2SO4−H2O and KNO3−NH4NO3−H2O at 298.15 K

For the equilibrium solid phases occurring in the systems: KCl?KBr?H₂O, K₂SO₄?(NH₄)₂SO₄?H₂O and KNO₃?NH₄NO₃?H₂O, the concentration dependencies of differential solution enthalpies, Δ_sol H ₂ for several crystallization paths, were measured. The limiting differential solution enthalpies, Δ_sol H ₂ ⁰ , were determined by extrapolation of the above dependencies to the ionic strength,I _m ⁰ , corresponding to the appropriate binary solutions. For KCl?KBr?H₂O system only, the clear dependence between Δ_sol H ₂ ⁰ andI _m ⁰ values was found and discussed.     

Cluster bonding and energetics of the borane anions,BnHn2− (n = 5–12): A comparative study using bond length—bond enthal

Cluster bond enthalpies, E_L(BB), and orders, n?(BB), for the structurally characterised closo anions, B_nH_n^2? (n = 6 and 8–12), have been estimated using the logarithmic length—enthalpy and enthalpy—order relationships E_L(BB) (kJ mol^?1) = 1.766 × 10¹¹ [L(BB)]^?4.0 and E_L(BB) (kJ mol^?1) = 318.8[n?(BB)]^0.697, respectively. In a parallel study, the molecular-orbital bond index CNDO-based calculation method has been used to give BB and BH bond indices, I(BB) and I(BH), from which bond index based bond enthalpies, E_I, have been calculated using the relationships E_I(BB) = 297.9 I(BB) and E_I(BH) = 374.8I(BH) (enthalpies in kJ mol^?1; lengths in pm). From these, total skeletal bond enthalpies Σ E(BB), and total bond enthalpies, Σ E(BB) + Σ E(BH), have been calculated. Although calculated values of E_L and Σ E_L generally exceed those of E_I and Σ E_I by some 8% and calculated values of I generally exceed those of n? by a greater amount, the trends in these parameters for the series of B_nH_n^2? anions are very similar, showing the greater efficiency with which the n + 1 skeletal electron pairs are used as n increases. However, the two approaches differ in that, whereas the Σ E_I values suggest that the anions are all of comparable stability, the ΣE_L values clearly show B₆H₆^2?, B₁₀H₁₀^2? and B₁₂H₁₂^2? to be more stable than B₈H₈^2?, B₉H₉^2? and B₁₁H₁₁^2?. The interatomic distances in B₇H₇^2? and in the unknown B₅ H₅^2? are estimated and used to assess their relative stabilities. The E_L values suggest that B₇ H₇^2? is of comparable stability to B₈H₈^2? etc., but show B₅H₅^2? as relatively unstable. The E_I values suggest that both of these anions should be relatively stable members of the series of closo anions.     

Zwitterionic copper(I) π-complexes with monosubstituted alkynes. Synthesis and X-ray diffraction study of a π-complex of copper(I) chloride with 4-ethynyl-4-hydroxy-2,2,6,6-tetramethylpiperidinium chloride

The first mononuclear π-complex of copper(I) chloride with monosubstituted alkyne of the formula [(C₉H₁₆NH₂(OH)C≡CH)CuCl₂] was obtained in the system CuCl-HCl-H₂O-(C₉H₁₆NH₂(OH)C≡CH)Cl (C₉H₁₆NH ₂ ⁺ (OH)C≡CH is the 4-ethynyl-4-hydroxy-2,2,6,6-tetramethylpiperidinium cation) and studied by single-crystal X-ray and X-ray powder diffraction. The crystals are monoclinic: a = 16.868(8) Å, b = 13.177(8) Å, c = 13.32(1) Å, γ = 103.50(4)°, space group P2₁/b, Z = 8. The structure of the complex contains two crystallographically independent zwitterionic entities of the formula [(C₉H₁₆NH₂(OH)C≡CH)CuCl₂], which result from π-coordination of the potential π-bidentate bond C≡C of the organic cation to one Cu(I) atom of the inorganic anion CuCl ₂ ^? . The distances Cu-m (m is the midpoint of the C≡C bond) are 1.91(2) Å. Along with weak intermolecular hydrogen bonds ≡CH...Cl and intramolecular contacts OH...Cl, the structure is stabilized by a directed ionic interaction through strong NH...Cl bonds.     

Complexes [Cu(H2L)](NO3)2 and [Cu(H2L)Cl]2[CuCl2]Cl · 0.5H2O (H2L is chiral bis(menthane) propylenediaminodioxime): Synthesis and structure

The synthesis of the [Cu(H₂L)](NO₃)₂ complex (I) and of a mixed-valent complex [Cu(H₂L)Cl]₂[CuCl₂]Cl·0.5H₂O (II), where L is chiral bis(menthane) propylenediaminodioxime. According to the data of single-crystal X-ray diffraction analysis, compounds I and II have ionic structures. In complex cations, the Cu²⁺ ion coordinates four N atoms of tetradentate chelate ligand, namely, the H₂L molecule. The coordination surrounding of the Cu atom in I is a distorted square CuN₄, while in II, it is a distorted square pyramid CuN₄Cl. The complex anion [CuCl₂]^? in II has linear structure. The mutual arrangement of oxime groups in H₂L corresponds to amphi-configuration of a ligand and therefore, intramolecular hydrogen bond O...H-O are formed in H₂L. The complex cations in compound II are joined in dimers through hydrogen bonds Cl...H-O. The values μ_eff for I and II are equal to 1.82 and 2.82 μ_B, respectively.     

Synthesis and characterization of hybrid organic-inorganic, dimeric tungstoantimonate, {[Cu(En)2(H2O)]2[Cu4Na2(H2O)2(OH)2](α-SbW9O33)2}6?1

The copper-substituted tungstoantimonate(III) [Cu(En)₂(H₂O)₂]₂[Cu(En)₂(H₂O)]{[Cu(En)₂ (H₂O)]₂[Cu₄Na₂(H₂O)₂(OH)₂][(??-SbW₉O₃₃)₂]} · 3H₂O (I) (En = ethylenediamine) has been synthesized and characterized by IR spectrum, elemental analysis, and XPS. X-ray single-crystal analyses were carried out on I, which crystallizes in the triclinic system, space group P-1, with a = 13.071(2) ?, b = 14.434(2) ?, c = 15.729(2) ?, ?? = 83.004(3)°, ?? = 71.237(2)°, ?? = 74.787(2)°, and Z = 1. The title polyanion consists of two [??-SbW₉O₃₃]^9? trivacant moieties joined together by an annular [Cu₄Na₂(H₂O)₂(OH)₂]^8? unit leading to a sandwich-type structural framework. The central belt of I contains two crystallography unique Cu²⁺ and four disordered Cu²⁺/Na⁺ ions which reduce the symmetry of the polyanion to C _2??.     

Complexes of NS and NSO donor ligands. Nickel(II), copper(II) and cobalt(II) complexes of glyoxal bis(morpholineN-thiohydrazone) and diacetyl bis(morpholineN-thiohydrazone)

Summary Reactions of glyoxal bis(morpholineN-thiohydrazone), H₂gbmth, with NiCl₂·6H₂O, Ni(OAc)₂·4H₂O, Ni(acac)₂· H₂O, CuCl₂·2H₂O, Cu(OAc)₂·H₂O, Cu(acac)₂, CoCl₂· 6H₂O, Co(OAc)₂·4H₂O and Co(acac)₂·2H₂O yield complexes of the type [M(gbmth)], [M=Ni^II, Cu^II or Co^II]. Diacetyl reacts with morpholineN-thiohydrazide in the presence of nickel salts to yield [Ni^II(dbmth)], [Ni^II(dmth)(OAc)]H₂O and [Ni^II(Hdmth)(NH₃)Cl₂] involving N₂S₂ and NSO donor ligands. Copper and cobalt complexes of N₂S₂ and NSO donor ligands with compositions [Cu^II(dbmth)], [Co^II(dbmth)]·4H₂O and [Co^II(H₂dbmth)]Cl₂, have been isolated. The compounds have been characterised by elemental analyses, magnetic moments, molar conductance values and spectroscopic (electronic and infrared) data.     

A theoretical investigation on the structures of (NH3)·(H2SO4)·(H2O)0-14 clusters

Ternary clusters (NH₃)·(H₂SO₄)·(H₂O)_n have been widely studied. However, the structures and binding energies of relatively larger cluster (n > 6) remain unclear, which hinders the study of other interesting properties. Ternary clusters of (NH₃)·(H₂SO₄)·(H₂O)_n, n = 0-14, were investigated using MD simulations and quantum chemical calculations. For n = 1, a proton was transferred from H₂SO₄ to NH₃. For n = 10, both protons of H₂SO₄ were transferred to NH₃ and H₂O, respectively. The NH₄⁺ and HSO₄⁻ formed a contact ion-pair [NH₄⁺-HSO₄⁻] for n = 1-6 and a solvent separated ion-pair [NH₄⁺-H₂O-HSO₄⁻] for n = 7-9. Therefore, we observed two obvious transitions from neutral to single protonation (from H₂SO₄ to NH₃) to double protonation (from H₂SO₄ to NH₃ and H₂O) with increasing n. In general, the structures with single protonation and solvated ion-pair were higher in entropy than those with double protonation and contact ion-pair of single protonation and were thus preferred at higher temperature. As a result, the inversion between single and double protonated clusters was postponed until n = 12 according to the average binding Gibbs free energy at the normal condition. These results can serve as a good start point for studies of the other properties of these clusters and as a model for the solvation of the [H₂SO₄-NH₃] complex in bulk water.     

Supramolecular compounds of indium sulfates with nitrogen-containing cations

Compounds with a general formula [Cat][In(H₂O) _n (SO₄)₂] _x · mH₂O (where Cat = C(NH₂)₃, H(2,2′-Bipy), H₂(4,4′-Bipy), H₂[Py(CH₂)₃Py], and H₃N(CH₂)₆NH₃) were synthesized and identified from the elemental analysis, IR, and thermogravimetric analysis data. X-ray diffraction analysis of crystalline [C(NH₂)₃][In(H₂O)₂(SO₄)₂] complex showed that the polymer chains of In aquasulfate form ensembles with guanidinium ions. The structure of [H₂(4,4′-Bipy)][In₂(H₂O)₆(SO₄)₄] · 2H₂O consists of the dimeric anions of indium sulfate. The coordination sphere of In includes three O atoms of three SO₄ groups and three O atoms of water molecules. The dimers are united into framework by diprotonated Bipy cations.