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1.
The crystal structure of Ca9(Ca x Mg1–x )(AsO4)6(AsO3OH) withx 0.5 (a=10.73,c=37.74 Å; space group R3c-C 3v 6 ;Z=6) was solved from 985 independent X-ray intensities collected on a 4-circle diffractometer, and refined toR=5.7% for all data. This compound is isotypic to Ca9Mg(PO4)6(PO3OH), a structure of the whitlockite-type.
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2.
Two new compounds of the AxMOXO4 family, β-LiVOAsO4 and β-VOAsO4, have been synthesized by solid state reaction and electrochemical lithium deintercalation from β-LiVOAsO4, respectively. Both compounds are isostructural and are built like other β-VOXO4 (X=S, P) by (VO5) chains of distorted VO6 octahedra connected via corner-shared AsO4 tetrahedra. For β-LiVOAsO4 the additional Li+ ions occupy chains of edge-shared octahedra running perpendicularly to the (VO5) chains. The one-dimensional antiferromagnetic behavior suggested by the structure has been experimentaly confirmed. It is shown that lithium deintercalation occurs through a first-order transition at 4.02 V vs Li+/Li0. From chemical bond considerations it is shown why the redox potential of a given transition element M in a six-fold coordination involving (M=O)m+ units lies between those observed in oxides and in M2(XO4)3 compounds with (XO4)n oxo anions (X=S, P, As).  相似文献   

3.
The mixed mercury complexes (2XC6H4)2N3HgY (X=CH3, F, Cl, Br, I;Y=SC2H5, SC6H5, SeC6H5) have been prepared. Both the Hg–S and Hg–Se bonds and, in contrast to other mixed triazenato-mercury compounds, the triazenato-mercury bonds have been shown to be kinetically labile on the NMR time scale by means of77Se and199Hg NMR spectroscopy. Evidence has been obtained for the presence of (2XC6H4)2N3HgY together with HgY 2 and [(2XC6H4)2N3]2Hg in solution.
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4.
The systems CaHPO4−MHPO4−H2O (M=Sr, Ba) were studied at 50°C. ForM=Sr, the series of single phases, Ca1−xSrxHPO4 for 0.95<X<0.75 and CaxSr1−xHPO4 for 0.4<X<1 have been prepared. These solid solution were caracterized by their infrared spectra and their crystallographic unit cell parameters. ForM=Ba a new phase Ca2Ba(HPO4)3 has been determined. It was characterized by DRX, IR, ATD and chemical analyses.

Zusammenfassung Bei 50°C wurde das System CaHPO4−MHPO4−H2O (mitM=Sr, Ba) untersucht. FürM=Sr wurden Serien von Einzelphasen erhalten: Ca1−xSrxHPO4 für 0.95<X< 0.75 und CaxSr1−xHPO4 für 0.4<X<1. Diese Mischkristalle wurden anhand ihrer Infrarotspektren und ihrer kristallographischen Elementarzellenparameter charakterisiert. FürM=Ba wurde die neue Phase Ca2Ba(HPO4)3 ermittelt. Sie wurde mittels DRX, IR, ATD und chemischer Analyse charakterisiert.
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5.
The infrared andRaman spectra of theM(CH3)4 andM(CD3)4 species,M=Si, Ge, Sn and Pb, have been reinvestigated. The spectra of the mixed tetramethyl compounds (CH3)3 MCD3,M=Si, Ge, Sn and Pb, and of (CH3)2Si(CD3)2 and CH3Si(CD3)3 have been recorded in the gaseous (i.r.) and liquid states (Raman). The proposed assignment is supported by a normal coordinate analysis.
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6.
The high-resolution207Pb magnetic resonance spectra ofR 4–n PbX n (R=Methyl, Ethyl;X=h1-Cyclopentadienyl, Chloride;n=1, 2) have been studied at 16.72Mc. The207Pb- ·· -1H spin-spin coupling constants for the molecules described have been obtained by analysis of the first order NMR-patterns as AxByM and AxByCzM respectively. The experimental spectra have been verified by a computer simulation. The chemical shifts and coupling constants of the lead organyls investigated show similar dependences on moleculare structure as well as number and species of the substituents like analogous organotin compounds.
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7.
The crystal structures of five isotypic hexagonal compounds with general formulaMAs4O6 X [M=K, NH4;X=Cl, Br, I; space group: P622;Z=1] were determined from 370 single crystal X-ray data and refined toR values <0.05. The structure type is characterized by neutral charged [As2O3] sheets arranged parallel (00.1). The As atoms of neighbouring two sheets point to each other and the sheets are combined by interlayeredM andX atoms, respectively. TheM atoms are coordinated to twelve oxygen atoms, theX atoms are coordinated to twelve arsenic atoms. In both cases the coordination polyhedron is a hexagonal prism. The compounds were synthesized by thermal treatments of cubic As2O3 and potassium or ammonium haloids in a saturated aqueous solution of potassium acetate resp. ammonia [500 K, saturation vapour pressure].
Die Verbindungen KAs4O6 X (X=Cl, Br, I) und NH4As4O6 X (X=Br, I): Hydrothermalsynthese und Strukturbestimmung
Zusammenfassung Die Kristallstrukturen der fünf isotypen hexagonalen Verbindungen mit der allgemeinen FormelMAs4O6 X [M=K, NH4;X=Cl, Br, I; Raumgruppe: P622;Z=1] wurden anhand von 370 Einkristall-Röntgendaten bestimmt und aufR-Werte <0.05 verfeinert. Der Strukturtyp ist ausgezeichnet durch neutrale [As2O3]-Schichten, die parallel (00.1) angeordnet sind. Die As-Atome zweier benachbarter Schichten weisen jeweils aufeinander zu, und die Schichten selbst werden durch zwischengelagerteM- bzw.X-Atome verbunden. DieM-Atome werden jeweils von zwölf O-Atomen, dieX-Atome von zwölf As-Atomen umgeben. Das Koordinationspolyeder ist in beiden Fällen ein hexagonales Primsa. Die einzelnen Verbindungen wurden unter Hydrothermalbedingungen aus kubischem As2O3 und dem jeweiligen Kalium- oder Ammoniumhalogenid in einer gesättigten wäßrigen Lösung von Kaliumacetat bzw. Ammoniak synthetisiert (500 K, Sättigungsdampfdruck).
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8.
The Complexes [Pd(PEt 3)2 dtc]X (1) and Pd(PR 3)Xdtc (2, 3) (dtc=S2CNEt 3;X=Cl, Br, I;R=Et, Ph) have been prepared. Conductivity, susceptibility, UV and IR measurements show that the cations [Pd(PEt 3)2 dtc]+ of1 and the complexes2, 3 have square-planar structure.
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9.
Potentially bi- and tetra-dentateSchiff bases derived from salicylaldehyde react with hydrated uranyl salts to give complexes: UO2H2 LX 2, UO2H2 LX 2 and UO2(HL)2 X 2 [H2 L=N,N-propane-1,3-diylbis(salicylideneimine), H2 L=N,N-ethylenebis(salicylideneimine) and HL=N-phenylsalicylideneimine;X =Cl, Br, I, NO3 , ClO4 , and NCS]. Because of marked spectral similrities with the structurally known Ca(H2 L) (NO3)2, theSchiff bases are coordinated through the negatively charged phenolic oxygen atoms and not the nitrogen atoms of the azomethine groups which carry the protons transferred from phenolic groups on coordination. Halide, nitrate, perchlorate and thiocyanate groups are covalently bonded to the uranyl ion, resulting a 6-coordinated uranium ion in the halo and thiocyanato complexes and 8-coordinated in nitrato and perchlorato complexes.
Komplexe von Dioxouranyl(VI) mit zwitterionischen Formen von zwei- und vierzähnigen Schiff-Basen
Zusammenfassung Von Salizylaldehyd abgeleitete zwei- und vierzähnigeSchiff-Basen reagieren mit hydratisierten Uranylsalzen zu Komplexen folgenden Typs: UO2H2 LX 2, UO2H2 LX 2 und UO2(HL)2 X 2 [H2 L=N,N-Propan-1,3-diylbis(salicylidenimin), H2 L=N,N-Ethylen-bis(salicylidenimin) und HL=N-Phenylsalicylidenimin;X =Cl, Br, I, NO3 , ClO4 und NCS]. Auf Grund eindeutiger spektraler Ähnlichkeiten mit dem bekannten Ca(H2 L) (NO3)2 wird auf Koordination über die negativ geladenen phenolischen Sauerstoffatome (und nicht über die Azomethin-Stickstoffe) geschlossen. Die AnionenX sind kovalent an das Uranyl-Ion gebunden; damit ergibt sich ein hexakoordiniertes Uranyl-Ion für die Halogen- und Thiocyanat-Komplexe und Oktakoordination für die Nitrat- und Perchlorat-Komplexe.
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10.
The formation of SiSi-bonds by a photochemical reaction of silylmercury compounds is described. The silylmercury compounds [(X 3Si)3Si]2Hg (X=Cl, OCH3) were synthesized via theVyazankin Hydrid method with (X 3Si)3SiH and Bis(t-butyl)mercury. By UV-irradiation of these products in hexane as a solvent, the oligosilanes [(X 3Si)3Si]2 are formed in good yields. All these compounds are charactericed by spectroscopical methods.
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11.
The influence of NaClO4, NaCl and Na2SO4 on the oxidation of Fe(phen) 3 2+ by Ce(IV) was investigated by means of the stopped-flow method. At the concentrations range of NaClO4 and NaCl 0.1–1.0M the rate constant values decrease from 1.03·105 to 0.56·105M–1s–1 and from 1.08·105 to 0.81·105M–1s–1 respectively.In varying concentrations of Na2SO4 solutions (0.05–0.35M) the rate constant values decrease from 1.05·105M–1s–1 to 0.45·105M–1s–1.Taking into account the negative salt effect the mechanism of the reaction progress is proposed.
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12.
The hitherto unknown compound Ca3Ga4O9 was prepared and investigated by X-ray single crystal methods. Ca3Ga4O9 has orthorhombic symmetry:a=1435.8;b=1682.5;c=532.1 pm; space group C 2v 11 –Cmm2,Z=6. The tetrahedra network (circles of 4 and 5 GaO4-tetrahedra) and the surrounding of Ca2+ are described and discussed with respect to other oxogallates.
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13.
TlFeSe2 is monoclinic, space groupC2/mC 2h 3 ,a=11.973 Å,b=5.490 Å,c=7.110 Å, =118.2°,Z=4.TlFeS2 is isotypic witha=11.636 Å,b=5.304 Å,c=6.799 Å, =116.7°.The crystal structure of TlFeSe2 has been determined from single crystal diffractometer data. Isotypy of the sulfide has been confirmed from powder diffraction data. The crystal structure containing infinite linear chains of edgesharing FeX 4-tetrahedra, and its relationship to the thio- and selenoferrates of the alkali metals are discussed. The mineral raguinite is very probably isotypic to synthetic TlFeS2.
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14.
The vibrational (conventional and far-infrared) and diffuse-reflectance spectra in conjunction with magnetic susceptibility measurements over a temperature range down to liquid nitrogen temperature are reported and discussed for the complexes; [Mn(HPOX)2 X 2]; [Mn(HMPX)2 X 2]; [Fe(HPOX)(POX) X 2] and [Fe(HMPX)(MPX) X 2](whereHPOX=pyridine-2-aldoxime (C6H6N2O);POX=C6H5N2O;HMPX=6-Methylpyridine-2-aldoxime (C7H8N2O);MPX=C7H7N2O;X=Cl, Br, I, NO3, NCS, or OA c andX 2=SO4). On the basis of these physical studies a six-coordinated structure is suggested for the manganese(II) and iron(III) complexes.Mössbauer spectra, measured at room-temperature and liquid nitrogen temperature also indicated a six-coordinate geometry for iron(III) complexes.
Übergangsmetallkomplexe mit Oxim-enthaltenden Liganden, IX. Spektroskopische und magnetische Untersuchungen von Mn(II)- und Fe(II)-Komplexen mit Pyridin-2-aldoxim und 6-Methylpyridin-2-aldoxim
Zusammenfassung Es wurden Komplexe von Pyridin-2-aldoxim (HPOX) und 6-Methylpyridin-2-aldoxim (HMPX) vom Typ [Mn(HPOX)2 X 2], [Mn(HMPX)2 X 2], [Fe(HPOX)(POX)X 2] und [Fe(HMPX)(MPX)X 2] (X=Cl, Br, I, NO3, NCS, OA c;X 2=SO4) dargestellt. Die Diskussion erfolgt basierend auf Infrarot-spektroskopie (inklusive fernes IR), Messungen der magnetischen Suszeptibilität (Temp. bis zu fl. N2) undMössbauer-Spektroskopie.
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15.
Dehydrohalogenation and metallation of boranato-bis-trimethylphosphonium salts (1), using two equivalents of a lithiumalkyl in tetrahydrofuran, leads to a solvated organolithium reagent H2B[(CH3)2PCH2]2Li (3) which can be converted into a 1:1n1-complex with tetramethylethylenediamin (4).3 reacts with anhydrous metal(II) halides to form spirocyclic coordination compounds of the type H2B[(CH3)2PCH2]2 M[CH2P(CH3)2]2BH2 (5–9,M=Be, Mg, Zn, Cd, Hg). The reaction of [(CH3)3PBH2P(CH3)3]Br (1) with lithium tetramethylmetalates Li[M(CH3)4],M=Al, Ga, on heating in the absence of a solvent affords the metallocycles H2B[(CH3)2PCH2]2 M(CH3)2 (10, 11) with evolution of methane. The products can be sublimed from the reaction mixture. The proposed structures of the new compounds, with tetrahedrally coordinated central atoms and strong covalent metal-carbon interactions, are supported by mass, IR and1H,7Li,11B,13C, and31P NMR spectra. Compound9 represents a rare case of a tetracoordinate organomercurial, compound5 is the first nonionic tetraalkylberyllate.
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16.
Ion/molecule reactions of four coordinateSchiff base complexes under negative ion chemical ionization conditions have been studied. The complex metal ions consisted of cobalt(II), nickel(II) and copper(II).Schiff base ligands with different donor strengths were employed. The gas mixtures used contained 90% methane and 10% of the gases O2, NO or CO. The spectra showed intense molecular negative ions, formed by secondary electron capture processes. Secondary ions were formed via ion/molecule reactions between the parent molecular negative ion and added gas molecules to giveMLX ,X=O2, NO, CO;L=Schiff base ligand,M=Co(II) or Ni(II). Consistent with former investigations, secondary ion formation was not found for the copper compounds. Influence of the central metal ion as well as the ligand donor strength on the ion/molecule reactions are discussed. From the results obtained a mechanism of the secondary ion formation is suggested.
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17.
The vibrational spectra of C6D5PX 2, (C6D5)2PX (X=H, Cl), (C6D5)3P and of the Cyclophosphanes (PC6H5) n and (PC6D5) n (n=5, 6) are reported. The spectra of the phenylphosphorouscompound D (the structure beeing unknown) are given too. The C6H5/C6D5 isotopic shift data in the lower frequency-region (600–100 cm–1) (facilitating the recognition of vibrational coupling effects) are used for vibrational assignments.
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18.
The two new compounds, Sr4Cu3(AsO4)2(AsO3OH)4·3H2O (1) and Ba2Cu4(AsO4)2(AsO3OH)3(2), were synthesized under hydrothermal conditions. They represent previously unknown structure types and are the first compounds synthesized in the systems SrO/BaO-CuO-As2O5-H2O. Their crystal structures were determined by single-crystal X-ray diffraction [space group C2/c, a=18.536(4) Å, b=5.179(1) Å, c=24.898(5) Å, β=93.67(3)°, V=2344.0(8) Å3, Z=4 for 1; space group P42/n, a=7.775(1) Å, c=13.698(3) Å, V=828.1(2) Å3, Z=2 for 2]. The crystal structure of 1 is related to a group of compounds formed by Cu2+-(XO4)3− layers (X=P5+, As5+) linked by M cations (M=alkali, alkaline earth, Pb2+, or Ag+) and partly by hydrogen bonds. In 1, worth mentioning is the very short hydrogen bond length, D···A=2.477(3) Å. It is one of the examples of extremely short hydrogen bonds, where the donor and acceptor are crystallographically different. Compound 2 represents a layered structure consisting of Cu2O8 centrosymmetric dimers crosslinked by As1φ4 tetrahedra, where φ is O or OH, which are interconnected by Ba, As2 and hydrogen bonds to form a three-dimensional network. The layers are formed by Cu2O8 centrosymmetric dimers of CuO5 edge-sharing polyhedra, crosslinked by As1O4 tetrahedra. Vibrational spectra (FTIR and Raman) of both compounds are described. The spectroscopic manifestation of the very short hydrogen bond in 1, and ABC-like spectra in 2 were discussed.  相似文献   

19.
The P3-nortricyclane 4-methyl-1,2,6-triphosphatricyclo[2.2.1.02,6]heptane, CH3C(CH2P)3, (1), is synthesized in a better yield than earlier described from P4, a Na/K alloy, and CH3C(CH2Br)3 in boiling 1,2-dimethoxyethane. It reacts withM(CO)5 thf (M=Cr, W) in the molar ratios of 1:1, 1:2, and 1:3 to form the pentacarbonylmetal complexes CH3C(CH2P)3[M(CO)5] n [n=1, 2, 3;M=Cr (a), W (b)], (2 a, b–4 a, b).1 gives with Mo(CO)5 thf only mixtures of CH3C(CH2P)3[Mo(CO)5] n andcis-Mo(CO)4 derivatives, which were identified by their infrared active A1 v(CO) modes at 2075 and 2025 cm–1.All the new compounds have been characterized also by their1H{31P},31P{1H} NMR, IR,Raman, and mass spectra.
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20.
Mo2Cl4 Pic 4·CHCl3 (A) (Pic=4-methylpyridine) and Mo2Br4 Pic 4 (B) crystallize in the monoclinic space group.A inC2/c (No. 15) witha=15.175 (4),b=10.847 (2),c=19.946 (6) and =104.52 (2)°;D o=1.71 (2),D c =1.72 gcm–3 forZ=4.B inP2l/n (No. 14) witha=9.270 (3),b=16.614 (5),c=9.305 (3) and =91.96 (5)°;D o=2.03 (3),D c =2.05 gcm–3 forZ=2.Two halogens and 4-methylpyridines of the MoX 2 Pic 2 group are in the trans position. Mo–Mo bond lengths are 2.153 96) forA and 2.150 92) forB. Both molecules are situated on the inversion center resulting in the eclipsed configuration of the ligands around the molybdenum pair. The structure ofB has been refined to the conventionalR factors of 0.08 and 0.098. Disorder on the part of 4-methylpyridines and chloroform molecules stopped the refinement ofA at the endR value of 0.175.Mean Mo–X and Mo–N bonding distances are 2.40 (2), 2.25 (5) forA and 2.53 (3), 2.25 (1) forB.
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