bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Predictive Model for the Initial Droplet Size and Velocity Distributions in Sprays and Comparison with Experiments
Authors: Kim Woo Tae , Mitra Sushanta K. , Li Xianguo , Prociw L. A. , Hu T. C. J. 
Published: May 2003

AbstractThe distribution of sizes and velocities of droplets initially formed in sprays is an important piece of information needed in the spray modelling, because it defines the initial condition of the spray droplets in the predictive calculations of the downstream two‐phase flow fields. A predictive model for the initial droplet size and velocity distributions in sprays is formulated in this study. The present model incorporates both the deterministic and the stochastic aspect of spray formation process. The deterministic aspect takes into account of the unstable wave motion before the liquid bulk breakup through the linear and nonlinear instability analysis, which provides information for the liquid bulk breakup length, the mass‐mean diameter and a prior distribution for the droplet sizes corresponding to the unstable wave growth of various wavelengths. The stochastic aspect deals with the final stage of droplet formation after the liquid bulk breakup by statistical means through the maximum entropy principle based on Bayesian entropy. The two sub‐models are coupled together by the various source terms signifying the liquid‐gas interaction, the mass mean diameter and the prior distribution based on the instability analysis. The initial droplet size and velocity distributions are measured experimentally by phase‐Doppler interferometry for sprays generated by a planar research nozzle and a practical gas turbine airblast nozzle. For the two nozzles, the liquid bulk sheet is formed before its breakup in a coflowing air stream. It is found that the model predictions are in satisfactory agreement with the experimental data for all the cases measured. Hence the present model may be applied to a variety of practical sprays to specify the initial conditions for the spray droplets formed in practical spray systems.
Two Heteroleptic Zinc(II) Complexes: [Zn(phen)(C9H15O6)2] and [Zn2(phen)2(H2O)2(C10H16O4)2] · 3H2O
Authors: Zheng Yue‐Qing , Lin Jian‐Li 
Published: May 2003

AbstractReactions of a freshly prepared Zn(OH)2‐2x(CO3)x · yH2O precipitate, phenanthroline with azelaic and sebacic acid in CH3OH/H2O afforded [Zn(phen)(C9H15O4)2] (1) and [Zn2(phen)2(H2O)2(C10H16O4)2] · 3H2O (2), respectively. They were structurally characterized by X‐ray diffraction methods. Compound 1 consists of complex molecules [Zn(phen)(C9H15O4)2] in which the Zn atoms are tetrahedrally coordinated by two N atoms of one phen ligand and two O atoms of different monodentate hydrogen azelaato groups. Intermolecular C(alkyl)‐H···π interactions and the intermolecular C(aryl)‐H···O and O‐H···O hydrogen bonds are responsible for the supramolecular assembly of the [Zn(phen)(C9H15O4)2] complexes. Compound 2 is built up from crystal H2O molecules and the centrosymmetric binuclear [Zn2(phen)2(H2O)2(C10H16O4)2] complex, in which two [Zn(phen)(H2O)]2+ moieties are bridged by two sebacato ligands. Through the intermolecular C(alkyl)‐H···O hydrogen bonds and π‐π stacking interactions, the binuclear complex molecules are assembled into layers, between which the lattice H2O molecules are sandwiched. Crystal data: (1) C2/c (no. 15), a = 13.887(2), b = 9.790(2), c = 22.887(3)Å, β = 107.05(1)°, U = 2974.8(8)Å3, Z = 4; (2) P1¯ (no. 2), a = 8.414(1), b = 10.679(1), c = 14.076(2)Å, α = 106.52(1)°, β = 91.56(1)°, γ = 99.09(1)°, U = 1193.9(2)Å3, Z = 1.
Syntheses, Crystal Structures, and Cytotoxicity Evaluation of two Chain‐like and Diamond‐like Silver(I) Complexes
Authors: Zhu Hai‐Liang , Zhang Xian‐Ming , Liu Gao‐Feng , Wang Da‐Qi 
Published: May 2003

AbstractTwo coordination polymers [Ag(dach)]n(NO3)n (1) and [Ag(teda)(F3CSO3)]n (2) (dach = 1, 2‐diaminocyclohexane, teda = 1, 4‐diazabicyclo[2.2.2]octane) have been synthesized and characterized by X‐ray single crystal analysis and cytotoxicity investigation. Compound 1 has a one‐dimensional chain‐like structure which is extended by ligand unsupported Ag···Ag interactions, hydrophobic interaction and hydrogen bonds into a three‐dimensional supramolecular array while compound 2 shows three‐dimensional diamond‐like framework constructed by coordination bonds. The high cytotoxities of these two compounds imply that they are potential candidates for antitumor agents.
Synthese und Kristallstruktur von Terbium(III)‐meta‐Oxoborat Tb(BO2)3 (≡ TbB3O6)
Authors: Nikelski Tanja , Schleid Thomas 
Published: May 2003

AbstractDas Terbium‐meta‐Oxoborat Tb(BO2)3 (≡ TbB3O6) entsteht einkristallin bei der Reaktion von Terbium, Tb4O7 und TbCl3 mit einem Überschuß von B2O3 in gasdicht verschlossenen Platinampullen nach drei Wochen bei 950 °C. Die Verbindung ist luft‐ und wasserstabil und fällt in langen, dünnen, farblosen Nadeln an, die aufgrund ihres ausgeprägt faserigen Habitus zur Wachstumsverzwillingung neigen. Die Kristallstruktur von Tb(BO2)3 (orthorhombisch, Pnma; a = 1598, 97(9), b = 741, 39(4), c = 1229, 58(7) pm; Z = 16) enthält parallel (100) verlaufende, stark gewellte Oxoborat‐Schichten {(BO2)‐} aus eckenverknüpften [BO4]5‐‐Tetraedern (d(B‐O) = 143‐154 pm, ∢(O‐B‐O) = 102‐115°). Die vier kristallographisch unterschiedlichen Tb3+‐Kationen weisen allesamt Koordinationszahlen von acht gegenüber den Sauerstoffatomen (d(Tb‐O) = 228‐287 pm) auf. Auch die entsprechenden Metallkationenpolyeder [TbO8]13+ treten zu Schichten (Zusammensetzung: {(Tb2O11)16‐}) zusammen, die sich ebenfalls parallel (100) ausbreiten.
Competitive Coordination of the Uranyl Ion by Perchlorate and Water ‐ The Crystal Structures of UO2(ClO4)2·3H2O and UO2(ClO4)2·5H2O and a Redetermination of UO2(ClO4)2·7H2O
Authors: Fischer Andreas 
Published: May 2003

AbstractBy slow evaporation of solutions containing UO2(ClO4)2 and an excess of HClO4, single crystals of [UO2(ClO4)2(H2O)3] (1) and [UO2(H2O)5](ClO4)2 (2) were obtained and their structures were determined. From similar solutions prepared from stoichiometric amounts of UO3 and perchloric acid, crystals of [UO2(H2O)5](ClO4)2·2H2O (3) were obtained. The trihydrate (monoclinic, P21/c, a = 545.44(1) pm, b = 1811.09(5) pm, c = 1032.46(2) pm, β = 90.016(1)°) consists of uranyl ions, which are coordinated by two monodentate perchlorate ions and three water molecules. The pentahydrate (monoclinic, P21/n, a = 529.35(2) pm, b = 1645.43(6) pm, c = 1480.18(6) pm, β = 99.847(1)°) contains uranyl ions coordinated by five water molecules. The same structural unit can be found in the heptahydrate, whose structure was re‐determined (orthorhombic, Pbcn, a = 920.9(3) pm, b = 1067.9(3) pm, c = 1445.7(3) pm). In this structure, two molecules of water of crystallization are present.
Der UCl3‐Typ mit komplexen Anionen und seine Additions‐Substitutions‐Variante: Synthese und Kristallstruktur von Nd(ClO4)3 und Na0, 75Nd0, 75(ReO4)3
Authors: Grupe Sven , Wickleder Mathias S. 
Published: May 2003

AbstractFliederfarbene Einkristalle von Nd(ClO4)3 (hexagonal, P63/m, Z = 2, a = 933, 0(1), c = 560, 08(5) pm, Rall = 0, 0422) bilden sich bei vorsichtiger Entwässerung von Nd(ClO4)3·6H2O im Argonstrom bei 220 °C. Hexagonale Einkristalle von Na0, 75Nd0, 75(ReO4)3 (P63/m, Z = 2, a = 1000, 0(1), c = 636, 08(5) pm, Rall = 0, 0206) sind ebenfalls fliederfarben und bilden sich bei der Umsetzung von Nd(ReO4)3 mit einem Überschuß von NaCl bei 820 °C. Phasenreine Pulverpräparate der Verbindung können durch Festkörperreaktion von NaReO4 mit Nd(ReO4)3 in evakuierten Quarzglasampullen erhalten werden.
Solution Mediated Synthesis and Structure of the First Anionic Bis‐( hexaborato)‐Zincate Prepared in the Presence of an Organic Amine
Authors: Natarajan Srinivasan , Klein Wilhelm , Panthöfer Martin , van Wüllen Leo , Jansen Martin 
Published: May 2003

AbstractA room temperature reaction of zinc acetate, tributyl borate and N, N, N′N′‐tetramethylethylenediamine (tmen) in a mixture of water and 1‐butanol has given rise to a new bis‐(hexaborato)‐zincate, [(Me)2NH(CH2)2NH(Me)2][{Zn(B6O7(OH)6}2]·2H2O (I). The structure, determined by single crystal X‐ray diffraction, (P1, a = 8.3014(2), b = 9.2489(2), c = 10.442(2)Å, α = 107.71(3), β = 94.22(3), γ = 100.02(3)°, V = 749.6(3)Å3 = Z = 1, R1 = 0.0387, wR2 = 0.105), consists of anionic molecular Zn hexaborate units forming a herringbone arrangement, through strong hydrogen bond interactions, with the amine molecule situated between the chains. Compound I is the first bis‐(hexaborato)‐zincate, to our knowledge, that has been synthesized in the presence of an organic amine.
Darstellung, Eigenschaften und Molekülstrukturen von Heterobimetallorganika des vierwertigen Germaniums mit dem 2‐(Dimethylaminomethyl)ferrocenyl‐Liganden FcN (η5‐C5H5)Fe[η5‐C5H3(CH2NMe2)‐2]
Authors: Fischer Axel , Jacob Klaus , Edelmann Frank Thomas 
Published: May 2003

AbstractDas heterobimetallische Lithiumorganyl [2‐(Dimethylaminomethyl)ferrocenyl]‐Lithium, FcNLi, reagiert mit Germanium(IV)‐chlorid, GeCl4, zu den heterobimetallischen Germaniumorganylen (FcN)nGeCl4‐n (n = 2 (1), 3 (2)). Bei Hydrolysereaktionen von 2 entsteht das heterobimetallische Organogermanol (FcN)3GeOH (3). Die eingehende Charakterisierung von 1—3 erfolgte durch Einkristall‐Röntgenstrukturanalysen sowie durch NMR‐ und Massenspektrometrie.
Alkoxo‐Verbindungen des dreiwertigen Eisen: Synthese und Charakterisierung von [Fe2(OtBu)6], [Fe2Cl2(OtBu)4], [Fe2Cl4(OtBu)2] und [N(nBu)4]2[Fe6OCl6(OMe)12]
Authors: Spandl Johann , Kusserow M. , Brüdgam I. 
Published: May 2003

AbstractDurch Reaktion von Eisen(III)‐chlorid in Diethylether mit Natrium‐tert‐butylat konnte das homoleptische dimere tert‐Butoxid [Fe2(OtBu)6] (1) hergestellt werden. Die Chloro‐Derivate [Fe2Cl2(OtBu)4] (2) und [Fe2Cl4(OtBu)2] (3) wurden durch Liganden‐Austausch zwischen 1 und Eisen(III)‐chlorid synthetisiert. In 1, 2 und 3 liegen jeweils zwei kantenverknüpfte Tetraeder mit zwei tert‐Butoxo‐Gruppen als Brückenliganden vor. Eine entscheidende Rolle für die Synthese von 1, 2 und 3 spielt das verwendete Lösungsmittel Diethylether, wobei sich primär das Dietherat des Eisen(III)‐chlorids FeCl3(OEt2)2 (4) bildet. Durch Reaktion von Eisen(III)‐chlorid mit Tetrabutylammoniummethoxid in Methanol konnte darüberhinaus ein Chloro‐Methoxo‐Oxo‐Hexaeisen‐Cluster [N(nBu)4]2[Fe6OCl6(OMe)12] (5) mit Tetrabutylammonium als Kation synthetisiert und strukturell charakterisiert werden.
Metallkomplexe naphthyl‐substituierter Thioharnstoffderivate
Authors: Schröder Uwe , Richter R. , Beyer L. , Angulo‐Cornejo J. , Lino‐Pacheco M. , Guillen A. 
Published: May 2003

AbstractEs wurden das Thioharnstoffderivat N, N‐Diethyl‐N′‐2‐naphthoylthioharnstoff (1) und drei N‐(Dialkylaminothiocarbonyl)‐N′‐(1‐naphthyl)‐arylamidine (2‐4) synthetisiert und mit diesen CuII‐, NiII‐ und PdII‐Komplexe dargestellt. Die röntgenstrukturanalytischen Untersuchungen zeigen, daß 1 mit CuII und NiII unter Deprotonierung neutrale Bischelate von nahezu quadratisch‐planarer Koordination mit einer cis‐Anordnung der O‐ und S‐Ligatoratome bildet. 2‐4 binden in deprotonierter Form über ihre N‐ und S‐Atome in 1, 3‐Stellung an CuII und PdII zu neutralen Bischelaten — im Fall von CuII mit verzerrt tetraedrischer Koordination. PdII wird quadratisch‐planar koordiniert und hat, offenbar aufgrund des sterischen Einflusses der 1‐Naphthylgruppen, eine trans‐Anordnung der N‐ und S‐Ligatoratome.
The Crystal Structure of Ba58Ga22F180O
Authors: Pierrard Angélique , Samouël Maurice , Gredin Patrick , Laval Jean‐Paul , de Kozak Ariel 
Published: May 2003

AbstractThe crystal structure of Ba58Ga22F180O is established by means of X‐ray single crystal diffraction. It is tetragonal: a = 22.033(1) Å, c = 17.626(1) Å, Z = 2. The structure is solved in the space group I4/mmm (n° 139), using 3219 independent reflections. It is mainly built from a deficient arrangement of fluorite‐type [FBa4] tetrahedra connected by edges and vertices which constitutes the skeleton of the structure, giving rise to large cavities in which lie isolated fluorine ions in tetrahedral and octahedral barium environment, isolated [F2Ba6] bitetrahedra, isolated barium ions in eight‐coordination of fluorine and a complex arrangement of isolated [GaF6] octahedra and isolated [Ga2F10O] bioctahedra.
Synthese und Kristallstruktur von [(n‐Bu)4N][W6Cl18]
Authors: Dill Simone , Ströbele Markus , Meyer H.‐Jürgen 
Published: May 2003

AbstractSynthesis and Crystal Structure of [(n‐Bu)4N][W6Cl18]Single‐crystals of [(n‐Bu)4N][W6Cl18] were obtained as thin needles by adding methanol to a solution of W6Cl18 and [(n‐Bu)4N]Cl in tetrahydrofuran. The structure was determined by single‐crystal X‐ray diffraction at 210 K. [(n‐Bu)4N][W6Cl18] crystallizes in the monoclinic space group C 2/c with Z = 8 and the lattice parameters a = 2175.6(1) pm, b = 1738.0(1) pm, c = 2160.36(9) pm, and β = 91.680(5) °. The crystal structure contains isolated [(W6Cl12i)Cl6a]— clusters and [(n‐Bu)4N]+ ions.
Synthesis of Ammonium‐ and 4‐Dimethylaminopyridinium Amidofluorophosphates and Crystal Structure of [DMAPH][PO2F(NH2)]
Authors: Sluka Radek , Vavříková Karla , Žák Zdirad , Černík Miloš 
Published: May 2003

AbstractNH4[PO2F(NH2)] has been prepared by the reaction of a betaine py·PO2F with excess ammonia in acetonitrile solution, while the ammonolysis of DMAP·PO2F with a stoichiometric amount of NH3 yields [DMAPH][PO2F(NH2)]. The crystal structure of the latter was determined by single‐crystal X‐ray diffraction, which revealed that the anions [PO2F(NH2)]— are linked to infinite chains by double N—H···O bridges. Additional strong N—H···O bridging bonds connect each anion with its [DMAPH]+ counterion. The formation of a new betaine NH3·PO2F in the solution of py·PO2F in liquid ammonia was proved by 31P NMR spectroscopy and by identification of its hydrolysis products.
Voltammetric and Spectroscopic Study of Chromium(III)/Picolinate Complexes
Authors: Parajón‐Costa Beatriz S. , Wagner Claudia C. , Baran Enrique J. 
Published: May 2003

AbstractThe electrochemical properties and the stability of the CrIII complexes [Cr(pic)3]·H2O and [Cr(pic)2(OH)]2·5H2O (Hpic = pyridine‐2‐carboxylic acid = picolinic acid) were investigated in DMF solutions by cyclic voltammetry, and complemented by electronic spectroscopy. The electrochemical results indicate that both compounds undergo a one‐electron reversible reduction process. The mononuclear species has a more accessible reduction potential than the binuclear one. In this last case, the observed one‐electron process can be ascribed to a considerable stabilization of the mixed valence CrIII/CrII species. Both complexes were also characterized by infrared and Raman spectroscopy.
Magnetic Exchange Interactions in Dinuclear Copper(II) and Nickel(II) Complexes with μ‐Oxalato Bridges. The Structure of μ‐Oxalato(O, O′, O″, O‴)‐bis{[1, 8‐di(2‐pyridyl)‐3, 6‐dithiaoctane‐N, N′, S, S′]nickel(II)} Dinitrate Dihydrate
Authors: Castiñeiras Alfonso , Domínguez Ricardo , Gómez‐Rodríguez Lourdes , Borrás Joaquín 
Published: May 2003

AbstractA copper(II) and two nickel(II) dinuclear oxalato‐bridged compounds of formulae [{Cu(bpdto)}2(μ‐ox)](ClO4)2 (1), [{Ni(bpdto)]2(μ‐ox)](ClO4)2(2), and [{Ni(bpdto)}2(μ‐ox)](NO3)2·2H2O (3), where bpdto = 1, 8‐bis(2‐pyridyl)‐3, 6‐dithiaoctane and ox = oxalate = C2O42— anion, have been synthesized and characterized. The crystal structure of 3 was determined by single‐crystal X‐ray analysis. It is a dinuclear complex with i symmetry in which the oxalate ligand is coordinated in bis(didentate) fashion to the inversion centre‐related nickel atoms. The distorted octahedral environment of each nickel atom is completed by two sulphur atoms in the equatorial plane and by two pyridyl nitrogen atoms in axial positions. Magnetic susceptibility measurements over the range 5 — 299K, show antiferromagnetic interactions that are weak in 1 (J = —12.8 cm—1) and strong in 2 and 3 (J = —37.8 and —40.9 cm—1, respectively), which in the case of 3 is in keeping with the observed structural parameters.
Mercurous Dimethylglyoximato Nitrate, Hg2(Dmg)2(NO3)2
Authors: Nockemann Peter , Meyer Gerd 
Published: May 2003

AbstractColourless needles of mercurous dimethylglyoximato nitrate, Hg2(Dmg)2(NO3)2, grow from a diluted nitric acid solution of mercurous nitrate and dimethylglyoxime. The crystal structure (triclinic, P1¯, a = 728.50(13), b = 1066.8(2), c = 1167.9(2) pm, α = 93.78(2)°, β = 94.16(2)°, γ = 98.61(2)°, Rall = 0, 0726) contains the cations [Hg2(Dmg)2]2+ and “non‐coordinating” (NO3)— anions. In the cation, two neutral dimethylglyoxime molecules coordinate bidentately with Hg—N distances in the narrow range of 236 to 239 pm to the mercurous ion, Hg22+, which exhibits a Hg—Hg bond distance of 252.23(8) pm).
Hg2(OH)[BF4], the First Basic Mercurous Tetrafluoroborate
Authors: Göbbels Dirk , Meyer Gerd 
Published: May 2003

AbstractThe first basic mercurous tetrafluoroborate, Hg2(OH)[BF4], was obtained through a synproportionation reaction of red mercuric oxide, HgO, and elemental mercury in a 35% solution of HBF4 in water as colourless single crystals. The crystal structure (orthorhombic, Pbca, Z = 8, a = 985.0(1), b = 991.0(1), c = 1141.0(2) pm) contains [(HO)1/2—Hg—Hg—(OH)1/2]+ zig‐zag chains that are further connected via weak Hg—OH interchain interactions to layers between which the [BF4]— are located in an up and down fashion.
Synthese und Molekülstrukturen von amido‐ und imidoverbrückten Clustern elektronenreicher Übergangsmetalle
Authors: Link Holger , Reiss Peter , Chitsaz Soheila , Pfistner Heike , Fenske Dieter 
Published: May 2003

AbstractWir berichten in diesem Article über Ergebnisse, die im Rahmen des DFG‐Schwerpunktprogramms “Nitridobrücken zwischen Übergangsmetallen und Hauptgruppenelementen” erhalten wurden. Durch Reaktionen von elektronenreichen Übergangsmetallverbindungen mit stannylierten bzw. lithiierten Derivaten des Stickstoffs in Anwesenheit von Phosphanen erhält man in unterschiedlichen organischen Lösungsmitteln eine große Anzahl von stickstoffverbrückten Übergangsmetallclustern. Die Strukturen der Verbindungen 1 — 27 konnten durch Einkristall‐Röntgenstrukturanalyse aufgeklärt werden.
Transition Metal Complexes Containing Functionalized Organoimido and Phosphaneiminato Ligands
Authors: Siemeling U. , Kölling L. , Kuhnert O. , Neumann B. , Stammler A. , Stammler H.‐G. , Fink G. , Kaminski E. , Kiefer A. , Schrock R. R. 
Published: May 2003

AbstractTwo different types of modified imido and phosphaneiminato ligands are investigated, namely chelate ligands and redox‐functionalised ligands. The first examples of di(organoimido)chromium as well as di(phosphaneiminato)titanium and niobium chelates are described. Furthermore, the first complexes containing redox‐functionalised organoimido ligands are presented, together with the first structurally characterised redox‐functionalised phosphaneiminato complex. Compounds of the type [(RN)2M(CH2Ph)2] (M = Cr, Mo) are used as catalysts for the (co‐)polymerisation of the polar olefins methyl methacrylate, acrylonitrile and vinyl acetate. A range of X‐ray crystal structure determinations provide clear evidence for the quantum‐chemical result that, similar to organoimido complexes, the potential energy well for the angle at the nitrogen atom is very shallow for phosphaneiminato complexes.
2‐Iminoimidazoline — starke Stickstoffbasen als Koordinationspartner in der Anorganischen Chemie
Authors: Kuhn Norbert , Göhner Martin , Grathwohl Martin , Wiethoff Jörg , Frenking Gernot , Chen Yu 
Published: May 2003

Abstract2‐Iminoimidazoline weisen, bedingt durch die Tendenz des Fünfringfragments zur Übernahme einer positiven Formalladung und die hieraus resultierende Ylid‐artige Bindungssituation, eine hohe Stickstoff‐Basizität auf; sie können als Neutral‐liganden, als 2+2‐Elektronendonatoren fungieren. Durch Deprotonierung sind hieraus die zugehörigen Anionen als potentielle 2+4‐Elektronendonatoren zugänglich.Wir beschreiben zunächst die Synthese und Charakterisierung der Titelverbindung 2‐Imino‐1, 3‐dimethylimidazolin (ImNH, 8) und ihres Anions 9. Nachfolgend werden deren Ligandeigenschaften an ausgewählten Beispielen der Koordinationsverbindungen der Haupt‐ und Nebengruppenelemente demonstriert. In einem dritten Abschnitt stellen wir Versuche zur Funktionalisierung der Iminoimidazoline vor in der Absicht, durch die Konstruktion hemilabil koordinierender Neutralliganden einen Beitrag zur katalyseorientierten Komplexchemie zu leisten.Die Ergebnisse von MO‐Berechnungen zur Interpretation der Bindungssituation werden experimentellen Befunden gegenübergestellt.
On the Donor Ability of the Phosphaneiminato Substituent and Cube Formation with Transition Metal Fragments
Authors: Schoeller Wolfgang W. 
Published: May 2003

AbstractThe particular role of the phosphaneiminato ligand as a donor is investigated for a) nitrenes (phosphinidenes) and carbenes and b) cubane formation with transition metals. Accordingly, and as shown for the case a) the ligand is a stronger π‐donor than an amino group and can be considered as a special case of imine‐type substituents. The latter are very effective in π‐donation. In the case b), i.e. the cubane formation with transition metals, one has to consider transition metals with a partially or completely filled d‐shell (with electrons). Hence depending on the transition metal, cubanes are build with weak ferromagnetic coupled or closed shell systems. For the cubanes with closed shell character the matter of insertion of halide anions is discussed. In the last chapter of the review the bond stretching in the dithionitrosyl complexes with rhenium is characterized.
Pentamethylcyclopentadienyl Halfsandwich Complexes of Vanadium and Tantalum with Amido‐, Imido‐ Nitrido‐ and Azido Ligands
Authors: Herberhold Max , Dietel Anna‐Maria , Goller Achim , Milius Wolfgang 
Published: May 2003

AbstractLithium bis(trimethylsilyl)amide, LiN(SiMe3)2, reacts with Cp*V(O)Cl2 and Cp*TaCl4 to give trimethylsilylimido complexes such as [Cp*V(NSiMe3)(μ‐NSiMe3)]2 (7) and Cp*Ta(Cl)(NSiMe3)[N(SiMe3)2] (19), respectively. Substitution of the chloro ligand in 19 by anionic groups leads to complexes with 3 different N‐containing ligands, Cp*Ta(X)(NSiMe3)[N(SiMe3)2] (X = N3 (20) or NPEt3 (21)).Complex 7 is air‐ and moisture‐sensitive, and several derivatives containing oxo and trimethylsiloxy ligands have been identified. Trimethylsilyl azide, Me3Si‐N3, is able to replace the oxygen‐containing ligands for azido ligands. The two complete series of bis(azido)‐bridged complexes, [Cp*VCln(N3)2‐n(μ‐N3)]2 (n = 2, 1, 0) and [Cp*TaCln(N3)3‐n(μ‐N3)]2(n = 3, 2, 1, 0), are accessible from the reactions of Cp*VCl3 and Cp*TaCl4, respectively, with trimethylsilyl azide.A bis(nitrido)‐bridged azido‐vanadium complex, [Cp*V(N3)(μ‐N)]2 (18), has also been obtained and structurally characterized.