Ionische Strukturen von 4- bzw. 5fach koordiniertem Silicium Neue ionische Festkörperstrukturen von 4- bzw. 5fach koordiniertem Silicium: [Me3Si(NMI)]+Cl−, [Me2HSi(NMI)2]+Cl−, [Me2Si(NMI)3]2+ 2 Cl−· NMI

Ionic Structures of 4- and 5-coordinated Silicon. Novel Ionic Crystal Structures of 4- and 5-coordinated Silicon: [Me₃Si(NMI)]⁺ Cl^?, [Me₂HSi(NMI)₂]⁺ Cl^?, [Me₂Si(NMI)₃]²⁺ 2 Cl^?. NMI Me₃SiCl forms with N-Methylimidazole (NMI) a crystalline 1:1-compound which is stable at room temperature. The X-ray single crystal investigation proves the ionic structure [Me₃Si(NMI)]⁺Cl^? 1 which is the result of the cleavage of the Si? Cl bond and the addition of an NMI-ring. The reaction of Me₂HSiCl with NMI (in the molar ratio of 1:2), under cleavage of the Si? Cl bond and co-ordination of two NMI rings, yields the compound [Me₂HSi(NMI)₂]⁺Cl^? 2 . The analogous reaction of Me₂SiCl₂ with NMI (molar ratio 2:1) leads to a compound which consists of Me₂SiCl₂ and NMI in the molar ratio of 1:2. During the sublimation single crystals of the compound [Me₂Si(NMI)₃]²⁺ 2 Cl^?. NMI 3 are formed.     

Synthese und Kristallstruktur des Kalium‐Iminophosphanids [K4(THF)3(Me3SiNPEt2)2(OSiMe2OSiMe2O)]2

The potassium iminophosphanide complex [K₄(thf)₃(Me₃SiNPEt₂)₂(OSiMe₂OSiMe₂O)]₂ has been obtained by a melt reaction of Me₃SiNPEt₃ with potassium hydride at 140 °C in the presence of silicon grease (—OSiMe₂—)_n and subsequent crystallization from thf solution. The colourless moisture sensitive single crystals are characterized by X‐ray diffraction: Space group P1¯, Z = 1, lattice dimensions at —70 °C: a = 1135.9(3), b = 1250.0(3), c = 1866.1(4) pm, α = 92.65(1)°, β = 100.80(1)°, γ = 93.57(1)°, R₁ = 0.0604. The centrosymmetric dimeric cluster aggregate is formed by two of the eight potassium ions which are connected with the central oxygen atom of both the (OSiMe₂OSiMe₂O)^2— chains as well as with one of their terminal O atoms each. The remaining potassium ions are connected with the phosphorus atoms of the iminophosphanide groups (Me₃SiNPEt₂)^— as well as with its nitrogen atoms. They are terminally solvated by thf molecules.     

1:1 Metal Complexes of Bivalent Cobalt,Nickel, Copper,Zink, and Cadmium with the Tripodal Ligand tris[2-(dimethylamino)ethyl]amine: Their stabilities and the X-ray crystal structure of its copper(II) complex sulfate

The complex formation by Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺, and Cd²⁺ with tris[2-(dimethylamino)ethyl]amine (N(CH₂CH₂NMe₂)₃, Me₆tren) was investigated at 25° and at an ionic strength of 1, using VIS spectroscopy and potentiometric measurements. The stability constants of these complexes are compared with those of tris(2-aminoethyl)amine (N(CH₂CH₂NH₂)₃, tren), obtained under the same conditions. The values of the constants for Me₆tren are much lower than those for tren, due to the bulky Me substituents. The values of the constants can be correlated with the ability of the individual metal ions to adopt coordination number 5. This appears to be easier for Cu²⁺ and Co²⁺ than for Cd²⁺ and Zn²⁺ and is very difficult for Ni²⁺. The 1:1 complexes [ML(H₂O)]²⁺ are monoprotonic acids whose pK_s values are similar or lower than those of the corresponding aquametal ions. The X-ray crystal structure of the copper(II) complex [Cu(SO₄)(Me₆tren)] · 8H₂O reveals pentacoordination at the central ion. The UV/VIS spectra of the aqueous solutions of the Co²⁺, Ni²⁺, and Cu²⁺ 1:1 complexes confirm that the same coordination number is present also in these complexes.     

Quantitative determination of site occupancy of multi-rare-earth elements doped into Ca2SnO4 phosphor by electron channeling microanalysis

X-ray fluorescence analysis based on electron channeling effects in transmission electron microscopy (TEM) was performed on Ca₂SnO₄ phosphor materials doped with Eu³⁺/Y³⁺ at various concentrations, which showed red photoluminescence associated with the ⁵D₀-⁷F₂ electric dipole transition of Eu³⁺ ions. The method provided direct information on which host element site dopant elements occupy, the results of which were compared with those of X-ray diffraction (XRD)-Rietveld analysis. The obtained results indicated that while it is not favorable for a part of Eu³⁺ to occupy the smaller Sn⁴⁺ site, this is still energetically better than creating Ca vacancies or any other of the possible charge balance mechanisms. The local lattice distortions associated with dopant impurities with different ionic radii were also examined by TEM-electron energy-loss spectroscopy (TEM-EELS). The change in PL intensity as a function of dopant concentration is discussed based on the experimental results, although the general concept of concentration quenching applies.     

Incorporation of Mg<Superscript>2+</Superscript>, Sr<Superscript>2+</Superscript>, Ba<Superscript>2+</Superscript> and Zn<Superscript>2+</Superscript> into aragonite and comparison with calcite

We have investigated the presence of foreign ions into the bulk structure and the external surfaces of aragonite using periodic ab-initio methods. Four cations isovalent to Ca²⁺ were studied: Mg²⁺, Sr²⁺, Ba²⁺ and Zn²⁺. The calculations were performed at structures (bulk, surface) that contain four and eight CaCO₃ units. Our results, at the Hartree-Fock level, show that the incorporation of those ions into aragonite depends strongly on their size. Mg²⁺ and Zn²⁺, due to their smaller size, can substitute Ca²⁺ ions in the crystal lattice while the incorporation of Sr²⁺ and Ba²⁺ into aragonite is energetically less favoured. Examination of the [011], [110] and [001] surfaces of aragonite revealed that the surface incorporation reduces the energetic cost for the larger ions. These systems provide challenging examples for most shape analysis methods applied in Mathematical Chemistry.     

Synthesis and spectral characteristics of Sr2Y8(SiO4)6O2: Eu polycrystals

Spectral-luminescent characteristics of Sr₂Y₈(SiO₄)₆O₂: Eu powder crystal phosphor with the apatite structure and high-intensity luminescence of Eu³⁺ ions have been studied. The charge state of europium in the samples has been characterized by means of X-ray L₃-adsorption spectroscopy. It was established that Eu³⁺ forms two types of optical centers. Besides, luminescence of Eu²⁺ions was found. Reduction Eu³⁺→Eu²⁺ was considered, which may be due to vacancy formation in the 4f crystal lattice position and to negative charge transfer by this vacancy to two ions. Thus, in the silicate lattice there exist inhomogeneously distributed oxygen-deficient centers, which are responsible for nonradiative transfer of excitation energy to Eu³⁺ and Eu²⁺ ions. To study electron-vibrational interactions in the crystal phosphor samples, their IR and Raman spectra were examined. In the luminescence spectrum of Eu²⁺, a series of low-intensity bands caused by interaction of the 4f⁶5d state of Eu²⁺ with silicate lattice vibrations was observed.     

Synthesis and reactivity of cyclo-tetra(stibinophosphonium) tetracations: redox and coordination chemistry of phosphine–antimony complexes

Reductive elimination of [R₃PPR₃]²⁺, [11(R)]²⁺, from the highly electrophilic Sb^III centres in [(R₃P)₃Sb]³⁺, [8(R)]³⁺, gives Sb^I containing cations [(R₃P)Sb]¹⁺, [9(R)]¹⁺, which assemble into frameworks identified as cyclo-tetra(stibinophosphonium) tetracations, [(R₃P)₄Sb₄]⁴⁺, [10(R)]⁴⁺. A phosphine catalyzed mechanism is proposed for conversion of fluoroantimony complexes [(R₃P)₂SbF]²⁺, [7(R)]²⁺, to [10(R)]⁴⁺, and the characterization of key intermediates is presented. The results constitute evidence of a novel ligand activation pathway for phosphines in the coordination sphere of hard, electron deficient acceptors. Characterization of the associated reactants and products supports earlier, albeit less definitive, detection of analogous phosphine ligand activation in Cu^III and Tl^III complexes, demonstrating that these prototypical ligands can behave simultaneously as reducing agents and σ donors towards a variety of hard acceptors. The reactivity of the parent cyclo-tetra(stibinophosphonium) tetracation, [10(Me)]⁴⁺, is directed by high charge concentration and strong polarization of the P–Sb bonds. The former explains the observed facility for reductive elimination to yield elemental antimony and the latter enabled activation of P–Cl and P–H bonds to give phosphinophosphonium cations, [Me₃PPR′2]¹⁺, including the first example of an H-phosphinophosphonium, [(Me₃P)P(H)R′]¹⁺, and 2-phosphino-1,3-diphosphonium cations, [(Me₃P)₂PR′]²⁺. Exchange of a phosphine ligand in [10(Me)]⁴⁺ with [nacnac]^1– gives [(Me₃P)₃Sb₄(nacnac)]³⁺, [15(Me)]³⁺, and with dmap gives [(Me₃P)₃Sb₄(dmap)]⁴⁺, [16]⁴⁺. The lability of P–Sb or Sb–Sb interactions in [10(Me)]⁴⁺ has also been illustrated by characterization of heteroleptically substituted derivatives featuring PMe₃ and PEt₃ ligands.     

十甲基五元瓜环与几种金属离子配合物的晶体结构

合成了3个十甲基五元瓜环(Me₁₀Q[5])分别与铷离子、铈离子水合物相互作用形成的配合物以及四氯锌根离子存在下形成的单晶体,并测定了其单晶结构。3个配合物均形成以Me₁₀Q[5]为“胶囊体”,水分子为“胶囊”芯材,金属离子或水分子为“胶囊盖”的“分子胶囊”结构,并通过配键或氢键组装形成一维超分子链结构实体。     

Organoplatinum compounds : III. [Me3PtCl04]4, preparative and structural aspects of a new organoplatinum cluster compound

Several methods for the preparation of Me₃PtClO₄ have been investigated: anhydrous, pure Me₃PtCl0₄ was obtained by treating AgClO₄ with Me₃PtI in dry benzene. The compound issensitive to moisture and explodes on heat or shock treatment. Molecular weight determination indicates a tetrameric structure [Me₃PtClO₄]₄, and spectroscopic data are consistent with this. Preliminary X-ray investigation of a single crystal indicates a crystal symmetry I_4I/amd (Schoenflies: D¹⁹_4h) with four [Me₃PtClO₄]₄ units in a tetragonal cell (a = b = 11.267(5); c = 25.09(1)) and local symmetry D_2d of the [Me₃PtCl0₄]₄ structure.     

Synthesis and structure of a binuclear ruthenium 4-chlorobenzamidato complex

The compound Ru₂Cl(4-Cl-C₆H₄CONH)₄ was prepared by reaction of Ru₂Cl(O₂CCH₃)₄ with 4-Cl-C₆H₄CONH₂ at 180°C. Crystals of the composition Ru₂Cl(4-Cl-C₆H₄CONH)₄CH₃OH were obtained by slow diffusion of CH₃OH containing Et₄NCl into a Me₂SO solution of the compound. The structure of the crystalline product, which loses solvent of crystallization on removal from the mother liquor, was solved by X-ray crystallography by mounting a single crystal in a capillary containing the mother liquor. The crystals belong to the space group P1? (triclinic crystal system) with a = 12.731(3) Å, b = 14.389(3) Å, c = 12.604(3) Å, α = 103.41(2)°, β = 106.43(2)°, γ = 64.90(2)°, V = 1988.6(8) ų and Z = 2. There are two half ruthenium dimers linked by a Cl atom and an uncoordinated solvent CH₃OH molecule per asymmetric unit. The ruthenium dimers lie on two centers of inversion at 0, 0, 0 and 1/2, 0, 0. The chloride ions bridge dinuclear cations in the crystal, forming infinite zigzag chains. The average Ru-Ru distance is 2.296[1] Å and each ruthenium atom has a RuClN₂O₂ coordination sphere where the average Ru′-Ru-Cl angle is virtually linear (175.68[6]°). The metal oxidation states in the complex are + 2 and + 3, giving an average value of + 2.5. The arrangement of four bridging 4-Cl-benzamidato ligands is of the 2 : 2 type. The average Ru-N, Ru-O, Ru-Cl distances and Ru(1)-Cl(1)-Ru(2) angle are 2.036[6] Å, 2.044[5] Å, 2.583[2] Å and 117.26(8)°, respectively. The IR spectrum of the compound shows two N-H stretches at 3380 and 3340 cm^?1. The electronic spectrum of the compound in Me₂SO exhibits bands at 558 nm (ε = 340 M^?1 cm^?1), 425 nm (1000) and 320 nm (22,700).     

Investigation of photocatalytic activity of metal-doped TiO2 nanoparticles prepared by Pechini method

M-doped TiO₂ (M = Ag²⁺, Al³⁺, Ce⁴⁺, Nb⁵⁺) with different dopant contents have been prepared by the Pechini method using titanium IV isopropoxide as precursor. The effect of doping concentration on the photocatalytic activity for methyl orange (MO) photodegradation was investigated using UV radiation. The photocatalysts were characterized by surface area, X-ray diffraction and UV–Vis diffuse reflectance spectroscopy. An increase in the photoactivity of TiO₂ nanoparticles was confirmed by MO photocatalytic degradation experiments, when the transition metal ions were incorporated into the semiconductor crystalline lattice, which could be attributed to an increase in the charge separation and reduction of e^?/h⁺ recombination as a function of the substitutional defect generated at very low levels.     

Comparative study on energetic distortions of SO42− ions matrix-isolated in compounds with kröhnkite-type chains,K2Me(CrO4)2·2H2O and Na2Me(SeO4)2·2H2O (Me = Mg,Co, Ni,Zn, Cd)

Infrared spectra of compounds with kröhnkite-type infinite octahedral–tetrahedral chains, K₂Me(CrO₄)₂·2H₂O and Na₂Me(SeO₄)₂·2H₂O (Me = Mg, Co, Ni, Zn, Cd), as well as infrared spectra of the title double salts containing matrix-isolated SO₄^2? guest ions are presented and discussed in the regions of the X–O stretching modes.The SO₄^2? guest ions matrix-isolated in selenate and chromate matrices exhibit four infrared bands corresponding to the four site-group components of the stretching modes in good agreement with the low site symmetry of the host ions (C₁ site symmetry). The values of Δν₃ (site-group splitting) and Δν_max (the difference between the highest and the lowest wavenumbered components of the stretching modes) are used as an adequate measure for the extent of energetic distortion of the matrix-isolated SO₄^2? guest ions.The influence of different crystal-chemical parameters (Me²⁺–OXO₃ bond strengths, sizes of the Me²⁺ and Me⁺ ions, electronic configurations of the Me²⁺ ions, hydrogen bond strengths, and unit-cell volumes of the host compounds) on the extent of energetic distortion of both the host SeO₄^2? and CrO₄^2? ions, and the SO₄^2? guest ions is analyzed. Correlations between the values of Δν₃ and Δν_max of the guest ions and both the degree of covalency of the respective Me²⁺–OXO₃ bonds and the electronic configurations of the Me²⁺ ions have been found and will be discussed. For example, the energetic distortion of SO₄^2? ions included in the chromate lattices decreases in the order Zn > Cd > Mg as a result of the decreasing covalency of the respective Me²⁺–O bonds in the same order (Δν₃ have values of 73, 58 and 36 cm^?1, respectively). Furthermore, the values of Δν₃ and Δν_max are larger when the metal ions have CFSE ≠ 0 (crystal field stabilization energy, Co²⁺, Ni²⁺). These cations are more resistant to angular deformations of the MeO₆ octahedra (i.e. changes in the O–Me–O bond angles), thus facilitating the extent of distortion of the matrix-isolated SO₄^2? ions as compared to those having CFSE = 0 (Mg²⁺, Zn²⁺ and Cd²⁺). For example, Δν₃ and Δν_max of SO₄^2? ions matrix-isolated in K₂Zn(CrO₄)₂·2H₂O have values of 73 and 163 cm^?1, and 116 and 207 cm^?1 in Na₂Zn(SeO₄)₂·2H₂O, whereas in the respective nickel lattices Δν₃ and Δν_max have values of 88 and 173 cm^?1 (K₂Ni(CrO₄)₂·2H₂O) and 127 and 212 cm^?1 (Na₂Ni(SeO₄)₂·2H₂O).The SO₄^2? guest ions included in selenate matrices, Na₂Me(SeO₄)₂·2H₂O, are remarkably much distorted than in chromate ones, K₂Me(CrO₄)₂·2H₂O, as deduced from the values of Δν₃ and Δν_max owing to a stronger static field caused by the smaller Na⁺ ions as compared to that caused by the larger K⁺ ions. The smaller unit-cell volumes of the selenate host compounds, i.e. the higher repulsion potential at the lattice sites at which the guest ions are situated additionally favor the extent of energetic distortion of the sulfate guest ions in the selenate matrices.     

Nitrosolates and related compounds—IX: Coordination compounds of divalent copper,nickel and cobalt with nitroacetate(2−) ions as chelating ligands. Crystal and molecular structure of potassium bis[nitroacetato(2−)]cuprate(II)-water (1/1)

The syntheses of K₂[Cu(nac)₂]·H₂O (4), [Cu(nac)(N-N)(H₂O)]·H₂O (N-N = bpy, phen; 5,6) and [M(nac)(N-N)₂]·xH₂O (M = Ni, Co; 7–10) with nitroacetate(2?) ions (nac^2?) as chelating ligands are described.The structure of 4 has been determined by single crystal X-ray diffraction and contains square planar [Cu(nac)₂]^2? units in which the nitro and carboxyl groups of the two chelate ligands are in cis positions. Two of the units form a centrosymmetric dimer with a four-membered CuOCu“O”-ring, the dimers being connected by exo-oxygens of the ligands into two-dimensional layers. The water molecules and the potassium ions are arranged between the layers; there are two kinds of potassium ions with distorted (1+4+1) and (2+4+3) coordinations respectively.     

Defect and dopant properties of the Aurivillius phase Bi4Ti3O12

Computer modelling techniques have been used to investigate the defect and oxygen transport properties of the Aurivillius phase Bi₄Ti₃O₁₂. A range of cation dopant substitutions has been considered including the incorporation of trivalent ions (M³⁺=Al, Ga and In). The substitution of In³⁺ onto the Bi site in the [Bi₂O₂] layer is predicted to be the most favourable. The calculations suggest that lanthanide (Ln³⁺) doping at the dilute limit preferentially occurs in the [Bi₂O₂] layer, with probable distribution over both the [Bi₂O₂] and the perovskite A-site at higher dopant levels. It is predicted that the reduction process involving Ti³⁺ and oxygen vacancy formation is energetically favourable. The energetics of oxide vacancy migration between various oxygen sites in the structure have been investigated.     

The nature and the mechanism of ion transfer in tungstates Me2+{WO4} (Ca, Sr, Ba) and Me 2 3+ {WO4}3 (Al, Sc, In) according to the data acquired by the tubandt method

The Tubandt method of electrolysis is used for studying the nature of ionic carriers in ceramics of tungstates Me²⁺{WO₄} (Ca, Sr, Ba) and Me ₂ ³⁺ {WO₄}₃ (Al, Sc, In) which are solid electrolytes. These compounds have the salt-like islet structure with isolated tetrahedrons {WO ₄ ^2? } and are crystallized in the allied structural types of scheelite (CaWO₄) for Me²⁺ and Sc tungstate (Sc₂{WO₄}₃) for Me³⁺. The electrolysis is carried out in 2- or 3-section cells (?)Pt|M ₂ ^n/n+ {WO₄}|Me ₂ ^n/n+ {WO₄}|Pt(+) in air atmosphere at the temperature of ～900°C and cell voltage of 4 and 300 V. All experiments without exception demonstrate a decrease in the mass of the cathodic section of cells. This points to the negative charge of ionic mass carriers and their transfer towards the Pt⁽⁺⁾ electrode. The cathodic briquette mass loss Δm ^(?) depends linearly on the charge passed through a cell. In all experiments with MeWO₄ tungstates, the anodic disk mass remains constant. The electrolysis of Me₂(WO₄)₃ cells is always accompanied by an increase in the anolyte mass Δm ⁽⁺⁾; however, in all experiments, Δm ^(?) > Δm ⁽⁺⁾. All data on mass variation and the results of studying the composition of nearelectrode electrolyte layers by XRD and SEM methods correspond to the condition $t_{WO_4^{2 - } } > t_C $ (C is the cation), i.e., {WO ₄ ^2? } anions pertain to the major ionic carriers. The transport number $t_{WO_4^{2 - } } $ is calculated based on the Faraday law from Δm ^(?). It is shown that the second ionic carrier with the mobility even higher than that of {WO ₄ ^2? } is the O^2? ion. For middle values of transport numbers, their ratio is shown to be $t_{O^{2 - } } $ (0.5–0.8) > (0.2–0.5) $t_{WO_4^{2 - } } $ . No results that would confirm the involvement of Me²⁺ and Me³⁺ ions in conduction are obtained.     

Crystal Structure and Magnetic Properties of Trinuclear Transition Metal Complexes (MnII,CoII, NiII and CuII) with Bridging Sulfonate-Functionalized 1,2,4-Triazole Derivatives

Here we present the synthesis, structure and magnetic properties of complexes of general formula (Mn)(Me₂NH₂)₄][Mn₃(μ-L)₆(H₂O)₆] and (Me₂NH₂)₆[M₃(μ-L)₆(H₂O)₆] (M = Co^II, Ni^II and Cu^II); L⁻² = 4-(1,2,4-triazol-4-yl) ethanedisulfonate). The trinuclear polyanions were isolated as dimethylammonium salts, and their crystal structures determined by single crystal and powder X-ray diffraction data. The polyanionic part of these salts have the same molecular structure, which consists of a linear array of metal(II) ions linked by triple N1-N2-triazole bridges. In turn, the composition and crystal packing of the Mn^II salt differs from the rest of the complexes (with six dimethyl ammonia as countercations) in containing one Mn⁺² and four dimethyl ammonia as countercations. Magnetic data indicate dominant intramolecular antiferromagnetic interactions stabilizing a paramagnetic ground state. Susceptibility data have been successfully modeled with a simple isotropic Hamiltonian for a centrosymmetric linear trimer, H = −2J (S₁S₂ + S₂S₃) with super-exchange parameters J = −0.4 K for Mn^II, −7.5 K for Ni^II and −45 K for Cu^II complex. The magnetic properties of these complexes and their easy processing opens unique possibilities for their incorporation as magnetic molecular probes into such hybrid materials as magnetic/conducting multifunctional materials or as dopant for organic conducting polymers.     

A New Iodobismuthate-Based Hybrid Containing Mixed Iodobismuthate Clusters Templated by Diammonium Cation: Structure and Photocurrent Response

A new iodobismuthate-based hybrid (Me₂DABCO)₇(BiI₆)₂(Bi₂I₉)₂.2I₃ (1) (Me₂DABCO²⁺ = N,N′-dimethyl-1,4- diazabicyclo[2.2.2] octane) has been structurally determined. The highly interesting feature of 1 lies in its presence of mixed types of iodobismuthate clusters, i.e. mononuclear (BiI₆)^3? and (Bi₂I₉)^3? dimer in one crystal lattice templated by Me₂DABCO²⁺ cation, which is the first example of mixed iodobismuthate clusters in one lattice. Its absorption zone can be broadened compared with other single iodobismuthate cluster-containing analogy compounds. And due to the strong I···I interactions, an optical gap of 1.61 eV can be observed. The photocurrent response properties before and after heating were discussed, which suggests that the device can be potentially used as temperature-response switch.     

Chemical composition and crystal structure of β-alumina type R+-gallate (R+ = K+, NH+4)

The crystal structures of β-alumina type K⁺-gallate (K⁺-β-gallate), Mg²⁺-doped K⁺-β-gallate, and NH⁺₄-β-gallate were refined by the single crystal X-ray diffraction method. The positive charges of excess K⁺ ions in K⁺-β-gallate were compensated by O^2? ions in the mO site which coordinated with interstitial Ga³⁺ ions. The charge compensation mechanism mentioned above was changed by doping with Mg²⁺ ions. The excess charges in Mg²⁺-doped K⁺-β-gallate were compensated by the replacement of Mg²⁺ ions for Ga³⁺ ions at the middle of spinel block. No defects were found in NH⁺₄-β-gallate for the charge compensation, which was completely consistent with the result of thermal analysis that indicated a stoichiometric composition of NH⁺₄-β-gallate.     

A one-pot method to prepare the carbene complex [TpRhCl2(CHNiPr2)] from [TpRh(CO)2], CHCl3, and NHiPr2

The complex [Tp^Me₂,ClRh(CO)₂] reacts with chloroform to give quantitatively the rhodium(III) complex [Tp^Me₂,ClRhCl(CHCl₂)(CO)] resulting from the oxidative addition of a C-Cl bond. Further reaction with diisopropylamine gives the aminocarbene complex [Tp^Me₂,ClRhCl₂(CHNiPr₂)], whose X-ray crystal structure has been solved. Addition of an excess of diisopropylamine to [Tp^Me₂,ClRh(CO)₂] in chloroform provides directly [Tp^Me₂,ClRhCl₂(CHNiPr₂)].