Showing papers on "Isostructural published in 1996"
TL;DR: In this article, the reaction of M(II) acetate hydrate (M = Co, Ni, and Zn) with 1,3,5-benzenetricarboxylic acid yields a material formulated as M3(BTC)2·12H2O.
Abstract: The reaction of M(II) acetate hydrate (M = Co, Ni, and Zn) with 1,3,5-benzenetricarboxylic (BTC) acid yields a material formulated as M3(BTC)2·12H2O. These compounds are isostructural as revealed by their XRPD patterns and a single crystal structure analysis performed on the cobalt containing solid [monoclinic, space group C2, a = 17.482 (6) A, b = 12.963 (5) A, c = 6.559 (2) A, β = 112.04°, V = 1377.8 (8) A, Z = 4]. This solid is composed of zigzag chains of tetra-aqua cobalt(II) benzenetricarboxylate that are hydrogen-bonded to yield a tightly held 3-D network. Upon liberating 11 water ligands per formula unit a porous solid results, M3(BTC)2·H2O, which was found to reversibly and repeatedly bind water without destruction of the framework. The proposed 1-D channels of the monohydrate have a pore diameter of 4 × 5 A, which is typical of those observed in zeolites and molecular sieves. The successful inclusion of ammonia into the porous solid was demonstrated. Larger molecules and others without a reactiv...
759 citations
TL;DR: In this article, three lanthanide complexes with mellitic acid, including [Ce2{C6(COO)6}(H2O)8]·C6[COO]6]· H2O (1), [Eu2{c6(cOO) 6}(CO) 8]·H 2O (2) and [Yb2[C6COO 6](H 2 O)10]·2H2 O (3), have been synthesized and characterized by X-ray crystall
99 citations
TL;DR: Two synthetic routes to compounds (η5-C5H4SiMe3)2Ti(C⋮CSiMe3), which contain monomeric MR entities are described in this paper.
Abstract: Two synthetic routes to compounds [(η5-C5H4SiMe3)2Ti(C⋮CSiMe3)2]MR (abbreviated as [1·MR]; M = Cu: R = Me (5), CH2SiMe3 (6), Et (7), nBu (8), C(H)CH2 (9), C6H2Me3-2,4,6 (13), C6H4Me-4 (14), C6H4OMe-4 (15), C6H4NMe2-4 (16), C6H5 (17); M = Ag: R = C6H2Me3-2,4,6 (18)) are described. These compounds contain monomeric MR entities, which are η2-bonded by both alkyne ligands of the organometallic 3-titanio-1,4-pentadiyne [(η5-C5H4SiMe3)2Ti(C⋮CSiMe3)2] (1). The X-ray structures of 5, 13, and 18 have been solved. Crystals of 5 are monoclinic, space group C2/c, with a = 19.477(1) A, b = 10.3622(6) A, c = 16.395(1) A, β = 95.287(5)°, V = 3294.8(3) A3, Z = 4, and final R = 0.030 for 3232 reflections with F ≥ 4σ(F) and 240 parameters. Crystals of 13 are orthorhombic, space group Pbcn, with a = 12.4290(9) A, b = 19.8770(8) A, c = 15.532(1) A, V = 3837.2(4) A3, Z = 4, and final R = 0.026 for 3082 reflections with I ≥ 2.5σ(I) and 217 parameters. The mesitylcopper compound 13 is isostructural with the mesitylsilver comp...
89 citations
TL;DR: In this paper, the synthesis of three novel compounds of norfloxacin (nf) was reported and discussed, and their crystal structures are presented and discussed in the monoclinic space group P 21/c with a = 8.438(2), b = 14.281(3), c = 15.012(3).
89 citations
TL;DR: C60F18 has been prepared by reaction between [60]fullerene and potassium hexafluoroplatinate in a Knudsen cell contained within a mass spectrometer; characterisation by 19F NMR spectroscopy shows that the molecule has C3ν symmetry and is isostructural with C60H18 as discussed by the authors.
88 citations
TL;DR: A complete range of spinel-like solid solutions forms between Li4Ti5O12 and Zn2TiO4 over a range of intermediate compositions, Li133xZn2 − 2xTi1 + 067xO4(050 ⊽ x ⩽ 090), the solid solutions are primitive cubic, but for compositions to either side, they are face centred.
Abstract: A complete range of spinel-like solid solutions forms between Li4Ti5O12 and Zn2TiO4 Over a range of intermediate compositions, Li133xZn2 – 2xTi1 + 067xO4(050 ⩽ x ⩽ 090), the solid solutions are primitive cubic, but for compositions to either side, they are face centred Rietveld refinement of powder X-ray diffraction data shows that ordering of Li and Ti onto two sets of octahedral sites is responsible for the primitive structure; Li and Zn are disordered over the tetrahedral sites A fully ordered, ideal composition occurs at x = 075, Li2ZnTi3O8, which is isostructural with LiFe5O8 The phase diagram of the spinel join shows that the ordered, primitive cubic solid solutions transform to disordered, face-centred cubic solid solutions at high temperatures, with a maximum in the transition temperature at 1150 °C for x = 075 The subsolidus phase diagram Li2TiO3–TiO2–ZnO at 1150 °C has been determined
82 citations
TL;DR: Titanosilicate, a structural analogue of the mineral pharmacosiderite, was prepared in its potassium and cesium forms, and ion exchanged to obtain the acid form as mentioned in this paper.
Abstract: Titanosilicate, a structural analogue of the mineral pharmacosiderite, was prepared in its potassium and cesium forms, and the cesium form was ion exchanged to obtain the acid form. The alkali cation derivatives, HM3Ti4O4(SiO4)3·4H2O (M = K+, Cs+), as well as the acid form, H4Ti4O4(SiO4)3·8H2O, are isostructural with the mineral. They crystallize in the cubic space group P43m with a = 7.8212(2) A, a = 7.7644(3) A, a = 7.8214(6) A, and Z = 1 for the cesium, potassium, and proton phases, respectively. In the structure, four titanium octahedra link to form Ti4O4 cubes around the unit-cell corners, and silicate tetrahedra join the titanium octahedra in all three crystallographic directions to form a three-dimensional framework. These linkages create three-dimensional tunnel systems that are filled by water molecules and exchangeable ions. The charge-neutralizing protons in the acid form bond to the oxygens in the Ti4O4 unit. Among the four protons in this group, three exchange for the cesium or potassium cat...
78 citations
TL;DR: This is the first report of the crystal structure of an aluminophosphate material containing cyclobutylammonium or a mixture of cyclic amines, and Interestingly, UT-7 is observed to thermally transform in the solid state to an as yet unknown layered material that can be independently synthesized in a similar synthetic system.
Abstract: UT-7 and UT-8 (University of Toronto, structure numbers 7 and 8) are two novel aluminophosphate materials prepared under non-aqueous conditions. Their structures, extended in one and two dimensions, respectively, have been solved by single-crystal X-ray diffraction and characterized by a variety of methods including powder X-ray diffraction (PXRD), insitu high-temperature PXRD, thermogravimetric analysis (TGA), energy dispersive X-ray analysis (EDX), and scanning electron microscopy (SEM). UT-7 ([Al3P5O20H]5-[C7H13NH3+]5, triclinic space group P1, Z = 2, a = 10.118(3) A, b = 15.691(4) A, c = 18.117(3) A, α = 72.91(2)°, β = 85.18(2)°, γ = 79.49(2)°) is built of polymeric one-dimensional chain units, hydrogen-bonded into anionic layers that are charge-compensated by interlamellar cycloheptylammonium cations. UT-7 is isostructural to our previously discovered UT-3 chain structure, isolated in the analogous cyclopentylamine system. UT-8 ([Al3P4O16]3-[C4H7NH3+]2[C5H10NH2+], monoclinic space group P21, Z = 2, ...
72 citations
TL;DR: The diselenide (RSe)2 and its bromo derivative RSeBr were determined by X-ray crystallography as discussed by the authors, and the compounds were characterised by elemental analyses, mass, multinuclear NMR (1H, 13C, 77Se), IR, Fourier transform-Raman spectrometry and conductance measurements.
Abstract: Bis[(2-dimethylaminomethyl)phenyl] diselenide (RSe)2 was obtained by the organolithium route. It underwent facile reaction with stoichiometric amounts of bromine and iodine to give the corresponding arylselenium halides RSeBr and novel RSeI in which the selenium is covalently bonded to iodine. With an excess of bromine it gave the corresponding tribromide RSeBr3 but a similar reaction with iodine gave only RSeI. With diazomethane it gave the selenoether (RSe)2CH2 and with HCl the known bis(hydrochloride)(RSe)2·2HCl. A catalytic conversion of alkenes into allylic acetates using (RSe)2 was carried out. The compounds were characterised by elemental analyses, mass, multinuclear NMR (1H, 13C, 77Se), IR, Fourier-transform-Raman spectrometry and conductance measurements. The compound RSeBr3 shows evidence for the existence of Se ⋯ N interaction in solution and was found to equilibrate between co-ordinated and non-co-ordinated forms. The structures of the diselenide (RSe)2 and its bromo derivative RSeBr were determined by X-ray crystallography. The compounds are isostructural and exhibit Se ⋯ N intramolecular co-ordination. The Se atom has T-shaped three-co-ordination in both structures and the five-membered chelate rings formed by the Se, C and N atoms are puckered and exist in an envelope conformation. The Se ⋯ N interaction in RSeBr [Se–N 2.143(6)A] is, however, considerably stronger than that in (RSe)2[Se(1)–N(1) 2.856(3), Se(2)–N(2) 2.863(4)A].
70 citations
TL;DR: An X-ray crystallographic structure determination of a µ-azido azacryptate has confirmed the existence of collinear Cu-NNNN-Cu geometry.
Abstract: An X-ray crystallographic structure determination of a µ-azido azacryptate has confirmed the existence of collinear Cu–NNN–Cu geometry, earlier cited as the origin of unusual spectroscopy in dicopper µ-azido cryptates; the isoelectronic µ-cyanato cryptate is also isostructural.
67 citations
Abstract: A wide range of 17O-enriched phases ABO3 and A2BO3 (A = Li, Na, Ca, Sr, Ba, and La; B = Ti, Zr, Sn, Nb, and Al) and related compounds has been synthesized and studied using 17O magic angle spinning (MAS) NMR spectroscopy. In these highly ionic phases, the 17O electric field gradients are small, and as a result highly resolved NMR spectra that reveal subtle structural inequivalences are observed. For titanates and zirconates the 17O chemical shifts fall in distinct, well-defined regions (372−564 and 280−376 ppm, respectively). The ratio of isotropic 17O chemical shifts from isostructural titanates and zirconates with the same A cation is constant, and this ratio is close to the ratio of the polarizing powers of titanium and zirconium. The B cation appears to be the dominant influence in determining the 17O chemical shift in these compounds. Additionally the number of oxygen resonances and the shift difference between them increases as the symmetry of the structure decreases. 119Sn MAS NMR has been applied ...
TL;DR: In this paper, the acidity of the ligand p-nitrocalix[8]arene, n-LH8, was determined and its acidity constants were determined at 25°C in H2O/THF 70/30 v/v by a potentiometric method.
TL;DR: In this article, a single crystal X-ray structure analysis revealed that 1 and 2 are one-and three-electron oxidized derivatives of 0 and are isostructural with 0, which suggest that oxidation has occurred first at the aquated Mn(2) centres of 0.
TL;DR: In this paper, the reaction of elemental copper and either lanthanides or actinides in molten alkali metal/polychalcogenide salts, several new quaternary phases have been discovered.
Abstract: From the reaction of elemental copper and either lanthanides or actinides in molten alkali metal/polychalcogenide salts, several new quaternary phases have been discovered. Specifically, these phases are ACuM2Q6 (where A = K, M = La, Q = S; A = Cs, M = Ce, Q = S; or A = K, M = Ce, Q = Se) and ACuMQ3 (where A = Cs, M = Ce, Q = S; or A = K, M = U, Q = Se). The CsCuCe2S6 crystallizes in the orthorhombic space group Immm with a = 5.500(1) A, b = 22.45(1) A, c = 4.205(4) A. The KCuCe2Se6 is isostructural. The CsCuCeS3 crystallizes in the orthorhombic space group Cmcm with a = 4.024(2) A, b = 15.154(2) A, c = 10.353(3) A. The KCuUSe3 is isostructural. In ACuM2Q6, the lanthanides bond to a mixture of mono- and disulfides in a bicapped trigonal prismatic geometry; these polyhedra subsequently connect in two dimensions, forming layers equivalent to those seen in the ZrSe3 structure type with Cu+ atoms residing in tetrahedral sites within the layers and alkali cations in the interlayer gallery. The compounds of the...
TL;DR: In this article, a series of halomethyl cations were prepared and studied by 13C NMR spectroscopy, and their structures and 13c NMR chemical shifts were also calculated by ab initio/DFT/GIAO-MP2 methods.
Abstract: A series of halomethyl cations was prepared and studied by 13C NMR spectroscopy. Their structures and 13C NMR chemical shifts were also calculated by ab initio/DFT/GIAO-MP2 methods. The δ13C of trihalomethyl cations CX3+ (X = Cl, Br, I) and dimethylhalocarbenium ions Me2CX+ (X = F, Cl, Br) correlate well with the Pauling electronegativities of the halogen atoms and δ11B of the isostructural and isoelectronic boron halides as well as with the calculated charge of carbon atoms. The CF3+ cation was not observed, but a chemical shift of δ13C 150 is indicated by comparison with other experimentally observed trihalomethyl cations. GIAO-MP2 chemical shift calculations gave δ13C 169.2 for the CF3+ cation.
TL;DR: In this article, the rhodium containing polyoxometalate, [(WZnRhIII2)(ZnW9O34)2]10− was prepared by reaction of rhCl3 with RhCl3.
Abstract: The rhodium containing polyoxometalate, [(WZnRhIII2)(ZnW9O34)2]10− was prepared by reaction of [(WZn3)(ZnW9O34)2]12− with RhCl3. The X-ray diffraction showed this compound to be isostructural to other compounds of this series. This was confirmed by the IR spectra. The elementary analysis and cyclic voltammetry measurements indicated that the polyoxometalate was of high purity. Epoxidation of alkenes with 30% aqueous H2O2 in 1,2-dichloroethane/water biphasic systems using [(WZnRhIII2)(ZnW9O34)2]10− as catalyst showed high overall activity as compared to other noble metal substituted polyoxometalates of this series. The reactions were highly selective to epoxidation of cyclohexene and similar to previously reported [(WZnMnII2)(ZnW9O34)2]12−, except that hydrogen peroxide yields were measurably higher in the rhodium case. The [(WZnRhIII2)(ZnW9O34)2]10− catalyst appears to be stable under turnovers conditions. Using IR spectroscopy as a probe to compare active polyoxometalates (Rh and Mn) versus an inactive one (Zn), showed that in the former case peroxo-tungstate intermediates could be identified whereas for the inactive compound no such intermediate was observed. A possible mechanism taking into account reactivity, steric constraints and IR spectra assuming structural integrity under catalytic turnover conditions was put forth.
TL;DR: Two ternary nitrides were synthesized from the appropriate alkaline-earth-metal nitride and chromium metal or the chromium nitride, Cr2N, at high temperatures in sealed stainless-steel capsules.
Abstract: Two new ternary nitrides, Sr3CrN3 and Ba3CrN3, were synthesised from the appropriate alkaline-earth-metal nitride and chromium metal or the chromium nitride, Cr2N, at high temperatures in sealed stainless-steel capsules. Structure determination from single-crystal X-ray data showed them to be isostructural in the hexagonal space group P63/m, Z= 2, with lattice constants a= 7.724(2), c= 5.249(1)A for Sr3CrN3 and a= 8.201(2), c= 5.497(1)A for Ba3CrN3. The structures contain trigonal-planar [CrN3]6– anions and either Sr2+ or Ba2+ cations.
TL;DR: In this paper, the synthesis and structural characterization of trinuclear acetate clusters with solely divalent metal ions and a central μ3-OH ligand are reported, and the core consists of an antiferromagnetically coupled M3 unit with the metals arranged in the corners of an isosceles triangle.
Abstract: The synthesis and structural characterization of a new class of “basic” trinuclear acetate clusters with solely divalent metal ions and a central μ3-OH ligand are reported. These molecules with the [(py)5MII3(OAc)3(μ3-OH)(cat)] stoichiometry (M = Mn, Fe, Co, Ni) are X-ray isomorphous and isostructural and contain octahedrally coordinated metal ions. The core consists of an antiferromagnetically coupled M3 unit with the metals arranged in the corners of an isosceles triangle. Two of the M−M distances vary between 2.98 and 3.16 A, and the longer M−M distance is observed between 3.65 and 3.76 A. As expected from the relative ionic radius lengths, these distances increase gradually from Ni(II) to Mn(II).
TL;DR: In this paper, the synthesis and characterization of tetrakis((methylthio)methyl)borate; M = Fe, Co, Ni) complexes are reported, where the ligand provides tridentate, face-capping coordination to the divalent metal ion.
Abstract: The synthesis and characterization of a series of [RTt]2M (RTt- = tetrakis((methylthio)methyl)borate; M = Fe, Co, Ni) complexes are reported. Isostructural derivatives of the newly synthesized phenyltris((methylthio)methyl)borate (PhTt-) also have been prepared and characterized. In each case, the ligand provides tridentate, face-capping coordination to the divalent metal ion. The Fe(II) complexes exhibit spin-crossover behavior both in solution and in the solid state. For [PhTt]2Fe, the temperature dependence of μeff has been mapped between 5 K (1.3 μB) and 400 K (3.2 μB). The low-spin Co(II) derivatives exhibit characteristic axial EPR spectra; for [PhTt]2Co, g⊥ = 2.185, g∥ = 2.035, A⊥ = 55 G, and A∥ = 42 G. Using Oh Fe(II) and Co(II) derivatives as benchmarks, the ligand field strength imparted by these anions is significant and falls just below that of the neutral macrocycle 1,4,7-trithiacyclononane (ttcn). All complexes have been characterized by X-ray diffraction. X-ray data: [PhTt]2Fe·0.6Et2O, mon...
TL;DR: The complex fluorides, LiBaF3 and KMgF3, which are isostructural with perovskite phases, are hydrothermally synthesized at 120-240 °C and characterized by powder X-ray diffraction, thermogravimetric analysis, IR spectroscopy and scanning electron microscopy as mentioned in this paper.
TL;DR: In this article, X-ray diffraction studies of approximately 150 polycrystalline specimens at room temperature confirmed the existence of sixteen ternary compounds in the BaO-Fe2O3-TiO2ternary phase diagram.
TL;DR: In this article, the structure of Fe3(PO4)3F2, H3N(CH2)4NH3] has been determined by single-crystal X-ray diffraction.
TL;DR: The oxothio polyanions γ-[SiW10M2S2O38]6- (M = MoV, WV) as discussed by the authors were obtained through stereospecific addition of the dication [M 2S 2O2]2+ (m = Mo, W) to the divacant γ]-SiW 10O36]8-anion in dimethylformamide.
Abstract: The oxothio polyanions γ-[SiW10M2S2O38]6- (M = MoV, WV) were obtained through stereospecific addition of the dication [M2S2O2]2+ (M = Mo, W) to the divacant γ-[SiW10O36]8- anion in dimethylformamide. These compounds were isolated as crystals and are stable in usual organic solvents and in aqueous medium from pH = 1 to pH = 7. NEt4Cs3H2[SiW10Mo2S2O38]·6H2O (a γ-isomer derived from the α Keggin structure capped by the [Mo2S2O2]2+ fragment containing a metal−metal bond) crystallizes in the triclinic space group P1 with a = 12.050(3) A, b = 12.695(2) A, c = 20.111(4) A, α = 74.35(2)°, β = 86.83(2)°, γ = 63.50(2)°, Z = 2. NEt4Cs5[SiW12S2O38]·7H2O is isostructural and crystallizes in the triclinic space group P1 with a = 12.197(4) A, b = 12.714(3) A, c = 20.298(3) A, α = 74.75(1) A, β = 86.48(2)°, γ = 61.80(2)°, Z = 2. 183W NMR spectra of Li+ salts in aqueous solution agree with the solid state structures and reveal 100% purity for both anions. Polarographic, infrared and UV−vis data are also given.
TL;DR: Quantitative chemical analyses have been performed for the isoelectronic, trigonal pyramidal closo-clusters Sn (5)(2-), Sb(5)(3+), Tl( 5)(7-), Pb(4)(-), and Bi(5+), both with extended Hückel (eH) and Hartree-Fock (HF) methods and the results agree well with available experimental data.
Abstract: Pentabismuth(3+) tetrachlorogallate(III), (Bi53+)(GaCl4-)3, has been synthesized by reducing a BiCl3−GaCl3 melt with bismuth metal and the crystal structure refined from X-ray (Cu Kα1) powder diffraction data. The structure was found to belong to space group R-3c, with the lattice parameters a = 11.871(2) A and c = 30.101(3) A (Z = 6). It is isostructural with the previously characterized Bi5(AlCl4)3. An attempt to synthesise the antimony analogue Sb5(GaCl4)3 by reducing a SbCl3−GaCl3 mixture with gallium metal produced a black solid phase. The gallium content of this phase is consistent with the stoichiometry Sb5(GaCl4)3, and the Raman spectrum of the phase dissolved in SbCl3−GaCl3 comprises strong, low-frequency bands attributable to Sb−Sb stretch vibrations in Sb53+ or another reduced antimony species. Quantum chemical analyses have been performed for the isoelectronic, trigonal pyramidal closo-clusters Sn52-, Sb53+, Tl57-, Pb52-, and Bi53+, both with extended Huckel (eH) and Hartree−Fock (HF) methods....
TL;DR: In this paper, the crystal structure of the bromo compound has been solved, and the crystal structures of the pyridine-2-carbaldehyde thiosemicarbazone compound and the chloro compound have been characterized.
TL;DR: A single-crystal X-ray structural analysis of a colorless crystal of Na2[(Hamp)2Mo5O15]·6H2O [space group P3121, a = 27.494(2), c = 10.165(1) A, V = 6654.
Abstract: Na2[(Hamp)2Mo5O15]·6H2O (where amp is adenosine-5′-monophosphate) has been crystallized by acidifying a solution containing Na2MoO4·2H2O and adenosine-5′-monophosphoric acid (AMP = H2amp) to pH 3—4. A single-crystal X-ray structural analysis of a colorless crystal of Na2[(Hamp)2Mo5O15]·6H2O [space group P3121, a = 27.494(2), c = 10.165(1) A, V = 6654.5(9) A3, Z = 3, R = 0.086, and Rw = 0.073 for 1087 independent data with I < 3σ(I)] showed that the anion is coordinated by two amp-phosphate-O atoms. [(Hamp)2Mo5O15]2− is isostructural with [(OPO3)2Mo5O15]6−, in which two PO4 tetrahedra span either side of a ring of edge- and corner-linked MoO6 octahedra. Two [(Hamp)2Mo5O15]2− anions are connected with ionic bondings of the Oanion–Na–Owater–Na–Oanion linkage, to be oriented parallel to the c-axis. The adenine-base ring of the amp ligand is stacked by that of the neighboring anion at a distance of 3.4 A along the c-axis. The 13C and 31P NMR spectra of a solution containing Na2MoO4·2H2O and AMP at different pH...
TL;DR: The hydrothermal syntheses of a family of new alkali-metal/ammonium vanadium(V) methylphosphonates, M(VO(2), M(3)(PO(3)CH(3))(2) and NH(4) are described, and the structures of these phases are compared and contrasted with related layered phases based on the HTO motif.
Abstract: The hydrothermal syntheses of a family of new alkali-metal/ammonium vanadium(V) methylphosphonates, M(VO2)3(PO3CH3)2 (M = K, NH4, Rb, Tl), are described The crystal structures of K(VO2)3(PO3CH3)2 and NH4(VO2)3(PO3CH3)2 have been determined from single-crystal X-ray data Crystal data: K(VO2)3(PO3CH3)2, Mr = 47593, trigonal, R32 (No 155), a = 7139(3) A, c = 19109(5) A, Z = 3; NH4(VO2)3(PO3CH3)2, Mr = 45487, trigonal, R32 (No 155), a = 7150(3) A, c = 19459(5) A, Z = 3 These isostructural, noncentrosymmetric phases are built up from hexagonal tungsten oxide (HTO) like sheets of vertex-sharing VO6 octahedra, capped on both sides of the V/O sheets by PCH3 entities (as [PO3CH3]2- methylphosphonate groups) In both phases, the vanadium octahedra display a distinctive two short + two intermediate + two long V−O bond distance distribution within the VO6 unit Interlayer potassium or ammonium cations provide charge balance for the anionic (VO2)3(PO3CH3)2 sheets Powder X-ray, TGA, IR, and Raman data for
TL;DR: In this article, the reaction of closo-exo-4,5-Li(THF)2-1-Li (THF), 2-2,3-(SiMe3)2C2B4H4 with anhydrous LnCl3 (Ln = Sm, Gd, Tb, Dy, Ho), in a molar ratio of 2:1 in dry benzene (C6H6), produced the sandwiched paramagnetic species.
TL;DR: Evidence was obtained for several protonated and hydroxo species of the complexes of both divalent and trivalent metals, where the corresponding protonation constants decrease with increasing stability of the chelate, ML(n)(-)(4), where M(n)()(+) represent the metal ion.
Abstract: N,N‘-ethylenedi-l-cysteine (EC) and its indium(III) and gallium(III) complexes have been synthesized and characterized. The crystal structures of the ligand and the complexes have been determined by single-crystal X-ray diffraction. EC·2HBr·2H2O (C8H22Br2N2O6S2) crystallizes in the orthorhombic space group P21212 with a = 12.776(3) A, b = 13.735(2) A, c = 5.1340 (10) A, Z = 2, and V = 900.9(3) A3. The complexes Na[M(III)EC]·2H2O (C8H16MN2O6S2Na) are isostructural for M = In and Ga, crystallizing in the tetragonal space group P42212 with the following lattice constants for In, (Ga): a = 10.068(2) A, (9.802(2) A), b = 10.068(2) A, (9.802(2) A), c = 14.932(2) A, (15.170(11) A), Z = 4 (4), and V = 1513.6(5) A3, (1457.5(11) A3). In both metal complexes, the metal atoms (In and Ga) are coordinated by six donor atoms (N2S2O2) in distorted octahedral coordination geometries in which two sulfur atoms and two nitrogen atoms occupy the equatorial positions, and the axial positions are occupied by two oxygen atoms o...
TL;DR: In this article, it was shown that the Cs+ ion templates the same metal germanium sulfide open-framework as (CH3)4N+ (TMA+), and that metal complexing agents enhance crystal size by at least two orders of magnitude.
Abstract: Here we report on investigations that have revealed for the first time that the Cs+ ion templates the same metal germanium sulfide open-framework as (CH3)4N+ (TMA+), and that metal complexing agents enhance crystal size by at least two orders of magnitude. The synthesis, structures and thermal properties of Cs2FeGe4S10 ·× H2O and TMA2FeGe4S10 are also described. Both have 3D zinc blende-type open-framework structures. These materials have the same connectivity as TMA2MnGe4S10. The tetrahedral sites in the lattice are alternately substituted by pseudo-tetrahedral Fe2+ and adamantanoid Ge4S104- building blocks, covalently linked together by Fe(μ-S)Ge bridge bonds, to give a tetragonal unit cell. The charge-balance of the anionic framework [Fe-Ge4S10]2- is maintained by either Cs+ or TMA+ ions in the cavity spaces. Synthesis of these materials demonstrates an interesting example of a self-assembly process in which a 3D framework is built from molecular precursors. Water adsorption-desorption cycling from room temperature to 200 °C reveals framework flexibility between larger and smaller tetragonal unit cell 14 isotypes. The compound TMA2FeGe4S10 is stable in nitrogen at 350 °C and under vacuum at 450 °C. The corresponding temperatures for Cs2FeGe4S10 are 530 °C and 630°C; it is stable on cooling to room temperature under vacuum, and after subsequent exposure to air. Six hundred thirty degrees celsius is the highest recorded temperature at which the integrity of a non-oxide framework has been maintained. The framework stability and flexibility of “all-inorganic” Cs2FeGe4S10 provides an encouraging example for researchers interested in developing sulfide-based framework materials with practical applications.