Hydrazinium Ions Research Articles

Whither Second-Sphere Coordination?

Whither Second-Sphere Coordination?

Synthesis, Crystal structure and thermal reactivity of [(N2H5)2Mn0.20Ni0.80(C2O4)2](H2O)2: A novel precursor to nickel-manganese oxide

A novel solid solution precursor, [(N 2 H 5 ) 2 Mn 0.20 Ni 0.80 (C 2 O 4 ) 2 ](H 2 O) 2 has been prepared and characterized by hydrazine analysis, CHN analyses, infrared spectrum, thermal degradation studies and single-crystal X-ray diffraction analysis. The single-crystal X-ray analysis reveals that the complex is centro-symmetric with distorted octahedral geometry. The metal center is occupied by both Mn 2+ and Ni 2+ ions coordinated by four carboxylate oxygen atoms from two bidentate oxalate 2− anions and two axial hydrazinium ions through nitrogen atoms which clearly define the distorted octahedral structure. Simultaneous TG-DTA of the complex shows three steps decomposition resulting in the formation of the mixed metal oxide (MnNi 6 O 8 ) as an end product. The chemical composition of mixed metal oxide obtained was confirmed from energy dispersive X-ray (EDX) data. Atomic force microscopy (AFM) reveals that the nanocomposite is formed as aggregates. The zeta potential (ζ) value is 30.2 mV, which indicates the high stability of the oxide.

Structural Variations of 2D and 3D Lanthanide Oxalate Frameworks Hydrothermally Synthesized in the Presence of Hydrazinium Ions.

Depending on the nature of the 4f element, six different lanthanide oxalate families were hydrothermally synthesized in the presence of hydrazinium ions. Four of them correspond to the general formula N2H5[Ln(C2O4)2]·nH2O but have different structural formulas according to the number of coordinated water molecules or hydrazinium ions and the structural arrangement, N2H5[La(C2O4)2] (1); N2H5[{Ln2(N2H5)}(C2O4)4]·4H2O, Ln = Ce, Pr, Nd, and Sm (2); N2H5[{Ln(H2O)}(C2O4)2], Ln = Sm, Eu, Gd, Tb, Dy, and Ho (3); N2H5[Ln(C2O4)2]·nH2O, Ln = Yb, n = 3, and Lu, n = 2 (5). The two others do not contain hydrazinium ions. Compound 4, obtained only with Ln = Er and Tm, contains a neutral lanthanide oxalate arrangement, [{Ln(H2O)}2(C2O4)3]. Finally, in the experimental conditions, crystals of compound 6 were obtained only for Lu, [{Lu(H2O)2}2(C2O4)3]·2H2O. For Ln = La to Ho, with coordination number CN = 9, 3D oxalate-lanthanide anionic frameworks are formed for the largest Ln, from La to Sm, and 2D networks are obtained for the smaller, from Sm to Ho. For Ln = Er to Lu, with CN = 8, 3D oxalate-lanthanide frameworks are formed; a 2D network is obtained only for the smaller lanthanide, Lu. The structures of compounds 1, 3 for Ln = Tb (3-Tb) and Ho (3-Ho), 4 for Ln = Er (4-Er), 5 for Ln = Yb (5-Yb) and Lu (5-Lu), and (6) were determined from single-crystal X-ray diffraction data in space groups P21/c, Pbca, P21/n, Fddd and P1̅, respectively. Thermal behaviors were studied by thermogravimetric analysis and high temperature powder X-ray diffraction. Optical properties were measured by UV-vis and IR spectroscopy.

Simultaneous Analyses of Hydrazine Molecules and Hydrazinium Ions in Aqueous Solution and Adsorbed on Catalyst Surfaces by Near-infrared Spectroscopy

This study is the first approach to analyze hydrazine (N2H4) in aqueous solution as well as adsorbed on catalyst surfaces by NIR (near-infrared) spectroscopy. N2H4 molecule was observed at 4961 cm−...

Solid State Chemistry of Ten-Fold Coordinate Thorium(IV) Complexes with Oxalates in the Presence of Ammonium and Hydrazinium Ions

Double and triple thorium oxalates have been synthesized by successive evaporation of a solution of thorium nitrate, ammonium, or hydrazinium oxalate and hydrogen peroxide. Compounds M6Ca2Th2(C2O4)9·nH2O (M = NH4+, N2H5+) (1) were first accidentally obtained due to the unexpected presence of calcium as impurities in the thorium nitrate used. Further evaporation led to the M2Th2(C2O4)5·nH2O (M = NH4+, N2H5+) (2) precipitation. After an additional evaporation of 2 weeks, compounds (2) transform into M4Th(C2O4)4·nH2O (M = NH4+, N2H5+) (3). In the three compounds, thorium is coordinated by five bidentate oxalate ions. In (1) Th(C2O4)5 entities share an oxalate ion to form dimeric units further connected by Ca(C2O4)5 (M = NH4+) or Ca(C2O4)5(H2O) (M = N2H5+) entities to build three-dimensional (3D) frameworks. Compounds (2) exhibit a 3D honeycomb thorium oxalate framework. Compounds (3) contain chains of oxalate-shared Th(C2O4)5 entities, whereas, in solution, the compound (NH4)2Th2(C2O4)5·1.5H2O (2) reacts with oxalate ions and turns into compound (NH4)4Th(C2O4)4·4H2O (3); in the solid state the chains of the compound (3) condense to form the 3D framework of the compound (2) and release solid ammonium oxalate.

Hydrazinium-assisted stabilisation of methylammonium tin iodide for lead-free perovskite solar cells

Here we explore the effect of the partial substitution of univalent methylammonium cations (MA) with hydrazinium ions (HA) on the stability, morphology and photovoltaic performance of hybrid MA(1−x)HAxSnI3 systems.

Structural study of (N2H5,H)2.9U1.1Ce0.9(C2O4)5·10H2O from a conventional X-ray diffraction diagram obtained on a powder synthesized by a fast vortex process

In the context of research on U/minor actinides for nuclear fuel reprocessing in the transmutation process, developments are first studied with surrogates containing uranium and lanthanides to facilitate testing. The tests consist of precipitating and calcining a hydrazinium uranium/cerium oxalate. The structure of this oxalate had not been previously determined, but was necessary to validate the physicochemical mechanisms involved.The present study, firstly demonstrates the structural similarity of the U/Ce oxalate phase (N2H5,H)2.9U1.1Ce0.9(C2O4)5·10H2O, synthesized using a vortex precipitator for continuous synthesis of actinide oxalates, with previously known oxalates, crystallizing in P63/mmc symmetry, obtained by more classical methods.This fast precipitation process induces massive nucleation of fine powders. Their structural and microstructural determination confirms that the raw and dried phases belong to the same structural family as (NH4)2U2(C2O4)5·0.7H2O whose structure was described by Chapelet-Arab in P63/mmc symmetry, using single crystal data. However, they present an extended disorder inside the tunnels of the structure, even after drying at 100°C, between water and hydrazinium ions. This disorder is directly related to the fast vortex method.This structure determination can be used as a basis for further semi-quantitative analysis on the U/minor actinides products formed under various experimental conditions.

Synthesis, structure and properties of hydrazinium germanate pharmacosiderite, (N 2H 5) 3Ge 7O 15(OH)·2.5H 2O

The first hydrazinium-bearing zeolite-like compound, (N 2H 5) 3Ge 7O 15(OH)·2.5H 2O, has been synthesized by low-temperature hydrazine-induced hydrolysis of fluorogermanic acid, H 2GeF 6. The crystal structure of hydrazinium germanate has been solved by direct methods and refined by the Rietveld method. The compound is related to the pharmacosiderite structure type and possesses chemical properties inherited from the presence of hydrazinium ions in the structure. The germanate does not contain volatile- or acid-forming anions and is thermally stable up to 140 °C. These features allow considering the new compound as a stable, solid-supported hydrazine source, possibly being a safe alternative to vaporized hydrazine in heterogeneous solid/gas reactions.

New Lanthanide Oxalato-nitrates Crystallized From Acidic Solutions

AbstractTo identify the various oxalates and oxalato-nitrates likely to form during the nuclear fuel reprocessing we study crystallization of such compounds by various methods (slow diffusion, hydrothermal syntheses, in situ oxalate syntheses …), in different conditions and in presence of monovalent ions. In a first stage, lanthanides are used as surrogates of the actinides (III) radioactive elements. This communication reviews various lanthanides (III) compounds obtained by crystallization from nitric acid solution containing hydrazinium ions. Diethyl oxalate was used as a precursor for oxalate ions. A careful adjustment of the experimental conditions allowed us to synthesize single crystals of nitrates, oxalato-nitrates and oxalates with various ligand/Ln(III) ratio and containing nitrates as ligands or as counter ions. In all the compounds hydrazinium ions are present as counter ions. The crystal growth method is described and the crystal structures, determined by X-ray diffraction from single crystals, are discussed in terms of metal-oxalate frameworks.

Spectral, thermal, and X-ray studies on some new bis and tris-hydrazine and hydrazinium metal pyruvates

Some bis-hydrazine metal pyruvates of transition metal ions of the formula M[CH3COCOO]2 [N2H4]2, where M = Co, Ni, Zn or Cd, tris-hydrazine metal pyruvates of the formula M[CH3COCOO]2 [N2H4]3, where M = Co, Ni, Zn or Cd, and hydrazinium metal pyruvates [N2H5]2M[CH3COCOO]4, where M = Co or Ni have been prepared and the compositions of the complexes have been determined by chemical analysis. The magnetic moments and electronic spectra of the complexes suggest a high-spin octahedral geometry for them. Infrared spectral data of bis-hydrazine complexes indicate the bidentate bridging mode shown by hydrazine molecules and mono dentate coordination by pyruvate ions. However, in tris-hydrazine complexes the pyruvate ions are ionic in nature. In hydrazinium complexes two hydrazinium ions and four pyruvate ions show unidentate coordination mode resulting in six coordination around metal ions. Thermo gravimetry and differential thermal analysis in air reveal that most of the complexes decompose in one step to give the respective metal carbonate as the final residue. However, the hydrazinium complexes yield Co2O3 or NiO as the residue. The final residues were identified by their X-ray powder data. The X-ray powder diffraction patterns of each series of complexes reveal isomorphism among the series.

Spectral and thermal studies on new hydrazinium metal sulfite dihydrates

Some new hydrazinium transition metal sulfite dihydrate complexes of the formula (N2H5)2M(SO3)2(H2O)2 where M=Fe, Co, Ni, Cu and Zn have been prepared and characterized by hydrazine and metal analyses, magnetic studies, electronic and infrared spectra and thermal analysis. The magnetic studies coupled with electronic spectra of iron, cobalt, nickel and copper complexes indicate their high spin octahedral nature. However the zinc complex is diamagnetic and show only the charge transfer transition. The infrared spectra shows that both the hydrazinium ions are coordinated to the metal ions, the sulfite ions are present as bidentate ligand.

Crystal structure of new uranyl oxalates (NH4)2[UO2(C2O4)2· H2O]·2H2O and (NH4)2-x(N2H5)x[(UO2)2(C2O4)3]·3H2O (x=0 and x=1). Comparison with other uranyl oxalates

SummaryTwo new ammonium uranyl oxalates (NH4)2-[UO2(C2O4)2H2O]·2H2O (1) and (NH4)2[(UO2)2(C2O4)3]· 3H2O (2) and one mixed ammonium hydrazinium uranyl oxalate (NH4)(N2H5)[(UO2)2(C2O4)3]·3H2O (3) have been prepared. The crystal structures of the three compounds have been determined by single-crystal X-ray diffraction. The crystal structures were solved by the Patterson method and Fourier difference techniques, and refined by a least square method on the basis of F2for all unique reflections. Crystallographic data: 1, hexagonal, space group P6122,a=8.143(2) Å,c=36.179(18) Å,Z=6,R1= 0.0268 for 105 parameters with 1223 reflections withI≥ 2σ(I); 2, monoclinic, space groupP21/n,a=8.705(3) Å,b= 19.454(6) Å,c=5.5105(18) Å, β=101.741(5)°,Z=2,R1= 0.0314 for 139 parameters with 2059 reflections withI≥ 2σ(I); 3, monoclinic, space groupP21/n,a=8.958(3) Å,b=19.601(7) Å,c= 11.007(4) Å, β=112.928(5)°,Z=4,R1=0.0363 for 131 parameters with 3346 reflections withI≥ 2σ(I). The crystal structure of 1 contains [UO2(C2O4)2· H2O]2−anions, NH4+cations and water molecules. In the anion, the linear uranyl group is coordinated by two bidentate oxalate anions and one water molecule giving a pentagonal bipyramidal environment for the uranium atom. The structures of 2 and 3 consist of two-dimensional networks built from uranyl and oxalate ions forming hexagonal rings. The oxalate ions are tetradentate, each bridging two uranyl ions which are coordinated by three oxalate groups to give distorted hexagonal bipyramidal environments for the uranium atoms. In 3, the ammonium and hydrazinium ions are ordered in successive layers. The various possible coordinations for the uranyl cation and the great versatility of the oxalate anion are magnificently illustrated in the monovalent ion-uranyl double oxalates series and other structures are expected by the diversification of the synthesis methods and experimental conditions.

Modeling combustion of hydrazinium nitroformate

Combustion of hydrazinium nitroformate (HNF), N2H5C(NO2)3, has been modeled and the resultscompared with experimental observations including steady regression rate (pressure, initial temperature, and radiant flux sensitivities), surface temperature, and linear frequency response to radiation. The underlying philosophy of the approach is to compare HNF combustion with a wide range of experimental conditions as much as possible. The results indicate that HNF condensed-phase decomposition is overall slightly exothermic (increasing with pressure) with activation energy similar to that for proton transfer between hydrazinium and nitroformate ions. The gas-phase flame is highly exothermic (also slightly increasing with pressure) with low-activation energy, suggesting the gas-phase process is more like a lowenergy barrier (low Eg), chain-carrier process than a high-energy thermal process, similar to what has been suggested for nitrocellulose-nitroglycerine double-based propellant and for cyclo-tetramethylene-tetranitramine. For both of these materials, and now for HNF, the low-Eg model has been shown to be in good agreement with experimental data for both steady and unsteady burning rate. The model also demonstrates the ability to capture an importants manifestation of nonlinear combustion. The prediction of a stronginitial pressurization spike in a low L* (high dP/dt) end-burning (no cross-flow) motor with HNF propellant confirms our recent hypothesis that initial pressurization spikes may be due to nonlinear dynamic combustion in addition to (or instead of) erosive burning.

Chromous hydrazine sulfate.

The title compound, catena-poly[dihydraziniochromium(II)-di-mu-sulfato-O:O'], [Cr(N2H5)2(SO4)2], was studied at 100 K and contains chains of chromium(II) ions linked by pairs of sulfate anions and coordinated to hydrazinium ions. The unique Cr atom lies on an inversion centre. All five H atoms were experimentally located and are involved in hydrogen bonding to O atoms of the sulfate groups.

Low temperature dynamics of hydrazinium ions in lithium hydrazinium sulphate (LHS) studied by electron spin echo (ESE) technique

The temperature dependence of the phase memory time T M in γ-irradiated lithium hydrazinium sulphate, LiN 2H 5SO 4, single crystal has been measured in the temperature range 4.2–290 K. Two minima in T M( T) at 115 and 175 K were observed. The low-temperature T M minimum has been identified as due to librational motions of the N 2H 5 + hydrazinium ion with an activation energy of 0.045 eV. The T M minimum at 175 K has been assigned to rotation of the –NH 3 + end of the hydrazinium ion with an activation energy of 0.074 eV. The activation energies have been compared with the results of a previous NMR and Raman spectroscopic studies of this crystal.

Acetate and malonate complexes of cobalt(II), nickel(II) and zinc(II) with hydrazinium cation

The hydrazinium(1+) metal acetates and malonate dihydrates of the molecular formula [(N2H5)2M(CH3COO)4] and (N2H5)2[M(OOCCH2COO)2(H2O)2] respectively, whereM=Co, Ni or Zn, have been prepared and characterized by chemical analyses, conductance, magnetic, spectral, thermal and X-ray powder diffraction studies. The magnetic moments and electronic spectra indicate that these complexes are of high-spin octahedral variety. The infrared spectra show that the hydrazinium ions are coordinated in the case of acetate complexes, whereas in the malonate complexes the hydrazinium ions are out side the coordination sphere. These complexes undergo exothermic decomposition in the temperature range 150–450°C to give the respective metal oxide as the final residue. The X-ray powder diffraction patterns of the malonate complexes indicate isomorphism among them.

Hydrazinium(1+) Hexafluorogallate(III) and Hydrazinium(2+) Aquapentafluorogallate(III)

(N2H5)3[GaF6] contains GaF63− octahedra arranged in a distorted cubic close-packed manner and linked to hydrazinium(1+) ions via N—H⋯F hydrogen bonds. (N2H6)[GaF5(H2O)] contains [GaF5(H2O)]2− octahedra arranged in a similar distorted cubic close packing manner; in addition to N—H⋯F hydrogen bonds to hydrazinium(2+) ions, these octahedra are also linked directly via O—H⋯F hydrogen bonds.

Vibrational modes of hydrazine sulfate and deuterium-substituted single crystals

A single crystal study of hydrazine sulfate and deuterium-substituted hydrazine sulfate utilizing both polarized Raman and FT-IR reflectance spectroscopy is reported. External optic modes of the sulfate ion have been distinguished from those of the hydrazinium ion for the first time. Reflectance spectroscopy allowed the identification of the ν 3 modes of the sulfate ion in a spectral region containing the N-H bending and deformation modes of the hydrazinium ion. The spectroscopic data indicate a very slight degree of interionic coupling between the sulfate and hydrazinium ions. Transverse optic modes derived from the reflectance spectra correspond quite well to the frequencies observed in the Raman spectra.

Influence of various additives on the sorption of cesium from strong nitric acid medium on potassium cupric ferrocyanide

The inhibitory action of hydrazinium or amidosulfate ion, whose presence prevented the oxidation of potassium cupric ferrocyanide with nitric acid and thereby kept the distribution coefficient of Cs on the sorbent at very high values in strong nitric acid medium, was eluciated to be due to the removal of nitrous acid present as an impurity. Based on this interpretation, a number of chemicals capable of reacting with nitrous acid were found to be effective as inhibitors besides hydrazinium and amidosulfate ions. A new process for Cs separation was proposed on the basis of the result obtained.

Structure and vibrational spectra of ammonium hydrazinium sulfate

The crystal structure of ammonium hydrazinium sulfate, (NH 4) 2N 2H 6(SO 4) 2, is reported for the first time. This compound crystallizes in a unimolecular unit cell in the triclinic space group P 1 with a = 5.600, b = 5.595, c = 8.608 Å, α = 72.47, β = 74.13 and γ = 66.14°. Hydrogen bonding is noted between the sulfate ion and both the ammonium and hydrazinium ions. The room temperature Raman and infrared spectra have been measured. Band assignments of internal and external optic modes are proposed, aided by comparison with spectra of the parent compounds, ammonium sulfate and hydrazinium sulfate. A differential scanning calorimetry measurement indicates phase transitions at 56 and 125°C.