Go toArchive
Browse byFacets
Bookbag ( 0 )
'Clusters' in keywords
Results  11 Items
Sorted by   
Publication Year
2001 (2)
2000 (1)
1997 (1)
1995 (1)
1994 (1)
1992 (3)
1985 (1)
1979 (1)
1Author    AlexanderV. Shtemenko3, AlexanderA. Golichenko3, KonstantinV. DomasevitchbRequires cookie*
 Title    Synthesis of Novel Tetracarboxylato Dirhenium(III) Compounds and Crystal Structure of [Re2 (l-Adamantylcarboxylate)4Cl2] * 4 CHC13  
 Abstract    The coordination compounds o f the general formula Re2 (1^ 4X2 (X = Cl, Br; L = 1 -adamantyl-carboxylate and 1 -adamantylacetate) have been prepared and characterized by means of UV-VIS spectroscopy (20000 cm-1 , 6 —► 6*). The crystal and molecular structure of Re2(AdCOO)4Cl2 • 4 CHCI3 solvate was determined by X-ray diffraction. The units Re2(AdCOO)4Cl2 adopt a centrosymmetric dinuclear array with each metal atom coordinated in a distorted octahedron comprising one rhenium and one chlorine atoms (Re-Cl 2.505(2) A) and four carboxylate oxygen atoms in the equatorial plane. The rhenium-rhenium separation of 2.2300(5) A corre­ sponds to quadruple bond between the metal atoms. All R e-0 bonds have an almost uniform length (2.017(4) -2.032(4) A) and do not differ essentially from the parameters reported for related compounds. The closest environment of the Re2(AdCOO)4Cl2 molecules in the crystal comprises weak Cl— HC hydrogen bonds with the chloroform molecules and significantly shortened van der Waals contacts Cl— Cl, 3.46 A. 
  Reference    Z. Naturforsch. 56b, 381—385 (2001); received December 15 2000 
  Published    2001 
  Keywords    Rhenium, Clusters, Adamantane 
  Similar Items    Find
 TEI-XML for    default:Reihe_B/56/ZNB-2001-56b-0381.pdf 
 Identifier    ZNB-2001-56b-0381 
 Volume    56 
2Author    Andreas Nägele3, Cynthia Dayb, Abdessadek Lachgarb, H.-Jürgen Meyer3, Sonderdruckanforderungen An, ProfH. Dr, -J MeyerRequires cookie*
 Title    Interpenetrierende Clusterstränge in der Kristallstruktur von Ko,77Nb6Cl15 Interpenetrating Cluster Chains in the Structure of Ko.77Nb6Cl15  
 Abstract    The solid state reaction of KCl, NbCl5 and Nb powder at 760 °C yielded black crystals of KNb6Cl15. The structure of the compound has been determ ined using single-crystal X-ray m e­ thods. KNb6Cli5 crystallizes in the orthorhombic space group Pmma (no. 51) with lattice constants a = 1780.1(2), b = 1341.4(1), and c = 925.5(1) pm, Z = 4, and R1 = 0.039 for all 2727 observed reflec­ tions. [ (N ^ C l ^ C l ^ 3'3]-anions in the structure are linked via two Cla a bridges to form one set of li­ near and one set of kinked chains along the cry­ stallographic c and a directions. Four remaining Cla a bridges interconnect both sets of chains to a three-dim ensional network. The potassium occu­ pancy on a 4k site was refined to a value of 0.384(3) consistent with the formula K0 77Nb6C li5. Ternäre Niobchloride des Formeltyps A Nb6Cl15 wurden bereits verschiedentlich beschrieben. Ver­ bindungen mit A = Li [1] und Na [2] kristallisieren kubisch (Ia3d) mit identischen Schweratomstruk-turen. Die Alkalim etall-Ionen Li (KZ = 4) und Na (KZ = 6) besetzen in den Strukturen A N b6Cl15 aber unterschiedliche Splitlagen und sind dyna­ misch fehlgeordnet. Die V ertreter mit A = In und TI [3] kristallisieren orthorhombisch (Pmma). Ihre Kationen befinden sich in zweifach überdachten, würfelförmigen Cl-Umgebungen (KZ = 10). Die Kenntnis des Formeltyps A N b6Cl15 mit schweren Alkalim etallen ist noch unvollständig. Einkristall­ 
  Reference    Z. Naturforsch. 56b, 1238—1240 (2001); eingegangen am 26. Juli 2001 
  Published    2001 
  Keywords    Niobium, Chloride, Cluster 
  Similar Items    Find
 TEI-XML for    default:Reihe_B/56/ZNB-2001-56b-1238_n.pdf 
 Identifier    ZNB-2001-56b-1238_n 
 Volume    56 
3Author    N. B. Mikheev3, A. N. Kam, A. Rum, V. L. Novitschenko3, A. Simon, HjM. AttauschbRequires cookie*
 Title    Electrochemical Cocrystallization Experiments with Gd2Cl3  
 Abstract    G d2Cl3 is electrocrystallized from molten G dC l3 at 900 K with a current efficiency o f 70% referring to the reaction 2G d C l3 + 3 e -= G d2Cl3 + 3 C l-. The reaction is used to determine co­ crystallization coefficients for trivalent rare earths and actinoids (Y, Nd, Cm, Pu), divalent lanthanoids (Eu, Yb), and Sr. The oxidation potential for the above reaction is determined as 2.65 < E ° < 2.68 V. 
  Reference    Z. Naturforsch. 47b, 992—9 (1992); eingegangen am 17. Januar 1992 
  Published    1992 
  Keywords    Cluster, Electrochemical Reduction, Cocrystallization 
  Similar Items    Find
 TEI-XML for    default:Reihe_B/47/ZNB-1992-47b-0992.pdf 
 Identifier    ZNB-1992-47b-0992 
 Volume    47 
4Author    A. N. Ägele3, E. A. Nokhinab, J. Sitarb, H.-JM. Eyer3, A. LachgarbRequires cookie*
 Title    Synthesis and Crystal Structures of ATi[Nb6Cli8] Compounds (A = K, Rb, Cs, In, Tl)  
 Abstract    New quaternary niobium cluster chlorides corresponding to the general formula ATi[Nb6Clis] (A = K, Rb, Cs, In, Tl) have been synthesized in sealed quartz tubes at 720 °C, starting from stoichiometric amounts of NbCls, niobium metal, TiCb, and AC1 (A = K, Rb, Cs), or In or Tl metals. The structures of RbTi[Nb6Clis] and CsTifNböClis] were determined using single­ crystal X-ray diffraction. RbTifNböClis] crystallizes in the rhombohedral crystal system, space group R3 (no. 148), Z = 3, with lattice parameters: a = 9.163(4), c = 25.014(14) A (hexagonal setting). The structure refinement converged to R] = 0.044 and wRi = 0.058 for all data. In this structure, discrete [NböClig]4-cluster units are linked by Rb+ and Ti3+ cations, located in a 12-coordinated anticubeoctahedral and octahedral chloride coordination environment, respectively. In contrast, CsTifNböClis] crystallizes in the trigonal crystal system, space group P31c (no. 163), Z = 2. The lattice parameters were determined to be a -9.1075(6), c = 17.0017(8) A. The structure refinement gives the reliability factors Ri = 0.029 and wRa = 0.063 for all data. The structure is built up of discrete octahedral [N bödis]4-cluster units, linked by Cs+ and Ti3+ cations which are located in a distorted hexagonal antiprismatic and octahedral chloride coordination environment, respectively. The structures of the compounds ATifNböClis] (A = K, In, Tl) were found to be isotypic with RbTi[NböCli8], and their unit cell parameters were refined using X-ray powder diffraction analysis. In tro d u ctio n 
  Reference    Z. Naturforsch. 55b, 139—144 (2000); received September 13 1999 
  Published    2000 
  Keywords    Niobium, Titanium, Cluster, Chlorides, Synthesis 
  Similar Items    Find
 TEI-XML for    default:Reihe_B/55/ZNB-2000-55b-0139.pdf 
 Identifier    ZNB-2000-55b-0139 
 Volume    55 
5Author    W. Scherzer, O. Krätzschmar, H. L. Selzle, E. W. SchlagRequires cookie*
 Title    Structural Isomers of the Benzene Dimer from Mass Selective Hole-Burning Spectroscopy  
 Abstract    Mass selected hole-burning experiments in the gas phase are presented for the benzene dimer formed in a supersonic jet expansion. The observed spectra show three different ground state configurations for the dimer. From isotopically substituted dimers the structure of the most prominent conformer could be assigned to a very floppy T-shape like structure with two non-equivalent sites for the benzene molecules. 
  Reference    Z. Naturforsch. 47a, 1248—1252 (1992) 
  Published    1992 
  Keywords    Benzene, Dimer, Cluster, Hole-burning spectroscopy, Mass spectroscopy 
  Similar Items    Find
 TEI-XML for    default:Reihe_A/47/ZNA-1992-47a-1248.pdf 
 Identifier    ZNA-1992-47a-1248 
 Volume    47 
6Author    Heinz Hoberg, Klaus Radine, Carl Krüger, MariaJ. RomãoRequires cookie*
 Title    Synthese neuer Phosphan-Nickel(I)-KompIexe und Kristallstruktur von /# 3 Jodo-fra-^-iodo-cycIotris(triphenylphosphan-nickel), (TPP) 3 Ni 3 I 4 Synthesis of New Phosphine Nickel(I) Complexes and Crystal Structure of // 3 -Iodo-m's-//-iodo-cyclotris(triphenylphosphine Nickel), (TPP) 3 Ni 3 I 4  
 Abstract    Synthesis and properties of the new nickel(I) complexes (COD)Ni(TPP)I (3) and (TCP)Nil (5) are reported. Reaction of 3 and 5 with diphenylacetylene (7) yields alkyne complexes (R 3 P)NiI(PhC2Ph)Ni(R 3 P)I (R = Ph (8a), and Cy (8b)). In solution, 3 disproportionates to give nickel(O) and (TPP) 3 Ni 3 I 4 (12)), the structure of which has been determined by X-ray crystallogra-phy. Cluster compound 12 is cleaved into monomeric units by addition of ligands such as TPP or CO (TPP = triphenylphosphine, TCP = tricyclohexylphosphine, COD = 1,5-cyclooctadiene). 
  Reference    Z. Naturforsch. 40b, 607—614 (1985); eingegangen am 17. Januar 1985 
  Published    1985 
  Keywords    Nickel(I), Alkyne Complex, Cluster, Crystal Structure 
  Similar Items    Find
 TEI-XML for    default:Reihe_B/40/ZNB-1985-40b-0607.pdf 
 Identifier    ZNB-1985-40b-0607 
 Volume    40 
7Author    DavidJ. Brauer, F. Rank, D. Örrenbach, Jörg Fischer, O. Thm, Ar StelzerRequires cookie*
 Title    Synthese von Phosphaalkenclustern durch reduktive Phosphinidenfragmentierung zweizähniger Halogenphosphane R X P -C H 2-P X R mit Fe2(CO) 9 Synthesis of Phosphaalkene Clusters by Reductive Phosphinidene Fragm entation of Bidentate Halogenphosphines R X P -C H 2-P X R with Fe2(CO)9 F rank Bitterer  
 Abstract    Reaction o f halogen functional m ethylenebisphosphines 1 X R P -C H 2-P R X (X = CI, Br) with excess Fe2(CO)9 affords /^-phosphinidene clusters (5) containing phosphaalkene ligands R -P = C H 2. The fragmentation o f the P -C -P skeletons in 1 proceeds stepwise, phosphido complexes 2 and novel Fe3 clusters 3 with R P -C H 2-P R bridging units being formed as inter­ mediates o f the oxidative addition reductive elim ination process. The X-ray structural analysis for 5 b (R = N E t2) reveals an Fe3(C O)9PR butterfly core to which the phosphaalkene ligand R -P = C H 2 (P = C bond length 1.766(4) Ä) is coordinated in a //3,^-m anner. In case o f meth­ ylenebisphosphines 1 with bulky substituents (R = 2,4,6-/Pr3C6H 2) the phosphinidene frag­ mentation o f the P -C -P skeleton is accompanied by the form ation o f 2,3-dihydrobenzo[b]-phosphole ligands. 
  Reference    Z. Naturforsch. 47b, 1529 (1992); eingegangen am 7. Januar 1992 
  Published    1992 
  Keywords    Phosphinidene Fragmentation, Bifunctional Chlorophosphines, D ehalogenation, Phosphaalkenes, Clusters 
  Similar Items    Find
 TEI-XML for    default:Reihe_B/47/ZNB-1992-47b-1529.pdf 
 Identifier    ZNB-1992-47b-1529 
 Volume    47 
8Author    DavidJ. Brauer, Jörg Fischer, Stefan Kucken, KlausP. Langhans, O. Thm, Ar Stelzer, Norbert WeferlingRequires cookie*
 Title    Wasserlösliche Phosphane, III [1] Wasserlösliche primäre Phosphane mit Ammoniumgruppierungen NR2R' in der Seitenkette -donorfunktionalisierte Amphiphile Water-Soluble Phosphanes, III [1] Water-Soluble Primary Phosphanes with Ammonium Groups NR2R' in the Side Chain -Donor-Functionalized Amphiphiles  
 Abstract    Primary and secondary aminoalkylphosphanes R2N -(C H 2)" ,-P H 2 (R 2 = Me2, «Bu2, C5H 10, C4H 80 , 2-(l-Methyl-2-pyrrolidinyl); m = 2, 3, 6, 10, 11; 1 -6) or [R2N -(C H 2)m]2PH (7, R2 = C5H 10; m = 2) are accessible by aminoalkylation of PH 3 with tö-chloroalkylamines R2N -(C H 2)m-C l in the superbasic medium DM SO/KOH (DM SO = dimethylsulfoxide). By selective N-quaternization of 1, 2, 4 -6 with RT (R ' = Me, C"H2" + 1; n = 6 -8 , 12, 16, 18) in the two-phase system CH2C12/H 20 novel primary phosphanes [R 'R 2N -(C H 2)m-P H 2]+I~ (ll-1 6 f) with quaternary ammonium groups in the alkyl side chain are obtained. The water solubility of l l -1 6 f decreases with increasing chain length (n) of R'. 11 (R = R' = Me; m = 2) shows a trans conformation at the C2H 4 bridge according to an X-ray structural analysis. Protonation of 1, 2, 4, 5 with HC1 affords the water-soluble hydrochlorides [HR2N -(C H 2)" ,-P H 2]+C1~ (19-22). The cationic primary phosphanes l l -1 6 f are stable towards oxygen. By oxidation of 11 with one or two equivalents of H 20 2 the primary phos­ phane oxide [Me3N -(C H 2)2-P (0) H 2]+I~ (23) or the phosphonous acid [Me3N -(C H 2)2-P (0)(0 H)H ]+I~ (23aj are formed. Hofmann degradation of 11 or 16c with KOH yields phosphirane in good yields. Reaction of 1, 2, 4 -6 (L) with Fe2(CO)9 at ambient temperature yields stable complexes (CO)4FeL (26-30). U nder more rigorous conditions Fe3 clusters (31, 32) with free R2N groups are obtained. 
  Reference    Z. Naturforsch. 49b, 1511—1524 (1994); eingegangen am 16. Mai 1994 
  Published    1994 
  Keywords    Aminoalkylphosphanes, Protonation, Water Solubility, Complexes, Clusters 
  Similar Items    Find
 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-1511.pdf 
 Identifier    ZNB-1994-49b-1511 
 Volume    49 
9Author    Achim Müller, Stephan Dillinger3, Erich Krickemeyer3, Hartmut Bögge3, Winfried Plass3, Anja Stammler3, RobertC. HaushalterbRequires cookie*
 Title    A Further Example for the Validity of the Concept of Unit Construction in Polyoxometalate Chemistry  
 Abstract    The compound Na7[NaC{(M 0V20 4)3()U2-0 H)3H(PhP03)4}2] • 2 N2H4-26 H20 (formu­ lation with respect to the aggregate in the crystal) has been synthesized and character­ ized by single-crystal X-ray structure analysis (which alone does not allow the determi­ nation of the formula), UV/Vis/NIR/IR, 31 P{1H}, 'H and 23Na NMR spectroscopy as well as magnetic susceptibility measurements. The compound is formed under similar conditions as (NH2Me2)6[H2C(Mov204)604(/i2-C)H)i2(MoVIC)3)4]-Correspondingly, both cluster frame­ works are built up by the same {(Mov204)3(/i2-OH)3}3+ units. 
  Reference    Z. Naturforsch. 52b, 1301—1306 (1997); received June 30 1997 
  Published    1997 
  Keywords    Cluster, Polyoxomolybdates, Self-assembly, Unit Construction, Electronic Structure 
  Similar Items    Find
 TEI-XML for    default:Reihe_B/52/ZNB-1997-52b-1301.pdf 
 Identifier    ZNB-1997-52b-1301 
 Volume    52 
10Author    A. Müller, S. Pohl, M. Dartmann, J. P. Cohen, J. M. Bennett, R. M. KirchnerRequires cookie*
 Title    Crystal Structure of (NH4)2[Mo3S(S2)6] Containing the Novel Isolated Cluster [MO3S13] 2  
 Abstract    The novel tri-nuclear metal-sulfur cluster [Mo3S(S2)6] 2 ~ can be obtained as its am-monium salt by the reaction of a Mo iv containing aqueous solutions with polysulfide. Its crystal and molecular structure has been determined by a single crystal X-ray study. The crystals are monoclinic (space group Cm, with a = 11.577(6) A, b = 16.448(7) Ä, c = 5.716(2) Ä, ß = 117.30(3)°, V = 967.2 A 3 , Z = 2, dexpti. = 2.54(2) g/cm 3 , dcai = 2.54 g/cm 3). The structure consists of isolated [Mo3S(S2)6] 2_ units, with three Mo atoms at the vertices of a triangle. There are bridging as well as terminal S2 2 ~-ligands lying above and below the Mo3-plane (bond distances: Mo-Mo = 2.722 A, Mo-S(terminal) = 2.435, Mo-S(bridging) = 2.452, Mo3-S = 2.353(4) A and S-S = 2.04 A (mean values)). Transition metal sulfur clusters are model com-pounds of bioinorganic interest [1, 2]. Isolated binary sulfur clusters were unknown until recently, though several halogen cluster compounds were reported. We were able to isolate the novel com-pound (NH4)2[Mo3S(S2)6] containing bridging as well as terminal S2 2_ -ligands in the molybdenum-sulfur-cluster anion [2]. In this paper the crystal structure of the compound is reported. Experimental 
  Reference    Z. Naturforsch. 34b, 434—436 (1979); received August 28/November 10 1978 
  Published    1979 
  Keywords    Crystal Structure, Molybdenum, Sulfur, Cluster, Metal-Metal Bond, Disulfide Diatomic Ligands 
  Similar Items    Find
 TEI-XML for    default:Reihe_B/34/ZNB-1979-34b-0434.pdf 
 Identifier    ZNB-1979-34b-0434 
 Volume    34 
11Author    Frank Steffen, G. Erd, MeyerRequires cookie*
 Title    [Er14(C2)2 (N )2 ] l24 -ein Iodid mit einem oligom eren, heterointerstitiellen Cluster [E r14(C2)2(N)2]l24 -an Iodide with an Oligomeric, H eterointerstitial Cluster  
 Abstract    [Er14(C2)2(N)2]l24 (triclinic, P I, a = 966.3(4) pm. b = 1027.6(2) pm. c = 1663.4(4) pm, « = 101.374(9)°, ß = 92.853(14)°, y = 112.83(2)°, Z = 2) is obtained as red-brown single crystals through a conproportionation reaction of E rl3 and erbium in the presence of carbon and N aN 3 in a sealed niobium container. It contains discrete, tetrameric [Er14(C2)2(N)2] clusters that are built from two octahedra and two tetrahedra connected via com ­ mon edges. The octahedral voids are filled with C2 units and the tetrahedral voids with N atoms. Each discrete [Erj4(C2)2(N)2] cluster is surroun­ ded by 32 iodide ligands which connect six clu­ sters via i-a and a-a bridges. 
  Reference    Z. Naturforsch. 50b, 1570—1573 (1995); eingegangen am 7. April 1995 
  Published    1995 
  Keywords    Rare Earth Elements, Halides, Cluster, Erbium Iodide Dicarbide Nitride, Crystal Structure 
  Similar Items    Find
 TEI-XML for    default:Reihe_B/50/ZNB-1995-50b-1570_n.pdf 
 Identifier    ZNB-1995-50b-1570_n 
 Volume    50