bluuebunny/crossref_metadata_2025_split huggingface dataset:
DSC and X-Ray Study on Gd2(MoO4)3
Authors: Flor G. , Berbenni V. , Marini A. , Massarotti V. , Riccardi R. 
Published: February 2015

Lattice parameters and thermal expansion of the three crystallographic modifications (α, β and β') of gadolinium molybdate have been determined.
The α-β and β'-β transitions have also been investigated by means of DSC and DTA measurements.
For the first one a transition enthalpy of 7.5 ± 0.5 kcal/mol was evaluated, while it was observed that factors such as the thermal history, the particle size and the heating/cooling rate affect the peak areas of the second one.
The results can be explained on the basis of the model proposed by Jeitschko for the β'-β transition provided that the necessary kinetic aspects are taken into account.
Electrolytic Conductivity of Pure and Doped Molten Silver Chloride
Authors: Greening Giorgio G. W. , Weil Konrad G. 
Published: February 2015

The electrolytic conductivity of pure molten silver chloride and of molten silver chloride doped with up to 2mole% of CaCl2, CdCl2, CsCl, LiCl has been measured in the temperature range 460°C to 620°C.
The changes in the conductivity of silver chloride when doped with ionic salts are found to be analogous to the conductivity changes found in binary alkali halide mixtures.
The Electromagnetic Rocket Gun Impact Fusion Driver
Authors: Winterberg F. 
Published: February 2015

An impact fusion driver is discussed which has the potential to accelerate a rocket-like small metallic projectile by a travelling magnetic wave to a few 100 km/sec over a reasonable distance. The propellant removes the heat produced in the projectile by resistive losses of the induced electric currents, and is thereby ejected from the projectile at a modest temperature. After having left the projectile, the propellant is shock-heated by the strong magnetic field of the travelling magnetic wave to high temperatures forming a high velocity jet. The total thrust on the projectile is the sum of the magnetic and recoil forces. In comparison to a rocket, the efficiency is much larger, with the momentum transferred to the gun barrel rather than to a tenuous jet.
To reach impact fusion velocities the accelerator would be a few 100 m long.
Polarized Low Temperature Luminescence of Single Crystal Pentacarbonylpyridinotungsten(0)-Complexes
Authors: Dillinger R. , Gliemann G. 
Published: February 2015

Polarized luminescence spectra of single crystal W (CO )5-X (with X = pyridine, 4-methylpyridine, 4-t-butylpyridine, 3,4-dimethylpyridine, 4-am inopyridine, 3-acetylpyridine, 3,5-dibromopyridine, 3-benzoylpyridine, 4-formylpyridine) at low temperatures (1.9 K≦ T ≦ 80 K) are reported.
Depending on the nature of the pyridine substituent the emitting state is either a ligand field (LF) state or a metal to ligand charge transfer (CT) state. This results in drastic differences in both bandshape and temperature behaviour of the luminescence spectra. The CT-luminescence is structureless and is not influenced by temperature variation, whereas the LF-lum inescence spectra exhibit in most cases a distinct vibrational fine structure at low temperatures and show a remarkable temperature dependence.
The emission spectra of single crystal W (CO )5-3,4-dim ethylpyridine and W (CO )5-pyridine can be strongly influenced by magnetic fields (H ≦ 6 T).
The results are explained within a model assuming molecular C4v symmetry and regarding spin orbit coupling.
Homology of Potential Energy Surfaces
Authors: Fernández Ariel 
Published: February 2015

It is shown that all the adjacency relations for the basins of attraction of stable chemical species and transition states can be derived from the topology of the pattern of intrinsic-reaction-coordinate- and-separatix trajectories in the nuclear configuration space.
The results are applied to thermal [1,3] sigmatropic rearrangements and they show that even the symmetry-forbidden path proceeds concertedly. The corresponding homological formulas giving the adjacency relations are derived.
Molekülinterne Dipolorientierung und dielektrische Absorption in verdünnter Lösung bei Mikro-und Submillimeterwellen. IV.Chlormethyl-Verbindungen
Authors: Klages Gerhard 
Published: February 2015

Abstract
The dielectric loss of eight molecules with the polar group in aromatic bonds and three in aliphatic bonds has been measured in very dilute solutions of cyclohexane at 20 °C. The measurements have been made at microwave frequencies in the range 2 to 130 GHz and at five wave numbers in the range 8 to 85 cm-1 (generated by a pumped molecular laser). These measurements are supplemented using a Fourier transform spectrometre up to 300 cm-1. The dielectric loss spectra ε″(γ̄) have been separated into a number of absorption regions (three or four in the microwave area) using the two variable Mori formalism. The power absorption spectra α(γ̄) are fitted to the Lorentzian shapes in order to determine the FIR resonances.
The dielectric dispersion step determined from loss measurements contains the contributions from all orientational processes of the permanent molecular dipole moment. The distribution of relaxation times indicates that the polar group reorientates by a fast intramolecular rotational process in five of the eight aromatic molecules investigated. Furthermore these five substances show character­istic broad resonance centred at approximately 39 cm-1. In order to determine the influence of the other substituted groups, the components of the dipole moment parallel and perpendicular to the internal axis of rotation are calculated from the dispersion steps. The perpendicular component does contribute as well to the Debye relaxation according to the Budo model as to the Poley and FIR absorptions. The relative magnitudes of these contributions are rather similar in the five molecules. In two other molecules, the intramolecular orientational process plays a relatively minor role due to the steric hindrance by a neighbouring group. However in dichloro-o-xylene, the two neighbour­ing groups do not prevent the fast process except that the net dipole moment is significantly reduced. Again, due to sterichindrance, the aliphatic bonded group molecules do not exhibit the fast dipolar orientational process or the characteristic resonance at 39 cm-1.
Amorphous Complexes MM (EDTA) (H2O)4 · 2H2O . LAXS and XPS Investigation of the Local Structure
Authors: Caminiti Ruggero , Roca Carmen Munoz , Beltran-Porter Daniel , Rossi Antonella 
Published: February 2015

Abstract
The amorphous MM (EDTA)(H2O)4·2 H2O (M = Ni,Co) substances are made up of infinite chains of alternating "hydrated" and "chelated" octahedra bridged by carboxylate groups: M(H2O)4 - M(EDTA)-M(H2O)4-... .
XPS enables to ascertain that the coordination of the EDTA ligand in the amorphous phase is identical to that in the crystalline phase, i.e., hexacoordination toward the M atom and two bridging groups in the Ni -Ni, Co - Co compounds.
The Effect of Deuteration on the Molecular Dipole Moments of Haloacetylenes
Authors: Heineking N. , Andresen U. , Dreizler H. 
Published: February 2015

Abstract
The dipole moments of chloro-, bromo-, and iodoacetylene, and those of the respective deuterated species, have been accurately determined using microwave Fourier transform spectrometers equipped with Stark cells. In each case, deuteration resulted in a change of the value of the dipole moment of about 0.012 D. The results provide strong evidence that the orientation of the dipole moment vector of iodoacetylene is opposite to that of the other haloacetylenes.
Über Metallalkyl- und -arylverbindungen, 51. Mittlg.* Unsymmetrische Diorganomagnesiumverbindungen. MgRR'(L) und solvensgetrennte Ionenpaare mit R = Me, Et, R' = Cyclopentadienyl, Indenyl, Fluorenyl, Phenylethinyl, L = Tetramethylethylendiamin, Pentamethyldiethylentriamin / On Metal Alkyl and Aryl Compounds, Part 51 Unsymmetrical Diorganomagnesium Compounds. MgRR'(L) and Solvens Separated Ion Pairs with R = Me, Et, R' = Cyclopentadienyl, Indenyl, Fluorenyl, Phenylethynyl, L = Tetramethylethylenediamine, Pentamethyldiethylenetriamine
Authors: Viebrock Heiko , Abein Dirk , Weiss Erwin 
Published: February 2015

Abstract
Amine adducts of diorganomagnesium compounds MgR2(L) are soluble in hydrocarbons and therefore valuable synthons for reactions in non-polar solvents. In this way unsymmetrically substituted derivatives MgRR'(L) become available by substituting one organic group by a different carbanion via acid-base reactions, according to eq. (1):
R2Mg(L) + HR' -> RR'Mg(L) + HR (1)
with HR' being stronger CH-acids than HR.
Using the amin adducts R2Mg(L) (R = Me, Et) with chelating amines (L = tetramethyl­ ethylenediamine, TMEDA, pentamethylethylenetriamine, PMDTA) and the strong CH-acids cyclopentadiene, indene, fluorene and alkynes the following compounds have been synthesized and their structures derived by X-ray analyses: MgMe(η3-cyclopentadienyl)(tmeda) (1), MgMe(η3-indenyl)(tmeda) (2), MgMe(η1-fluorenyl)(tmeda) (3), [Mg2Me2(pmdta)2]2+[fluorenyl]−
2
benzene (4) and [Mg2Et(phenylethynyl)3(tmeda)]2 ∙ benzene (5). It is remarkable, that cyclopentadienyl, indenyl, and fluorenyl ligands have a lower hapticity than η5 to the metal, due to steric repulsion by the other ligands. In 4 the bulky tridentate base PMDTA prevents any direct interaction between the fluorenide anion and magnesium, giving solvens separated ion pairs with the unusual and hitherto rare example of an organomagnesium cation [Mg2Me2(pmdt)2]2+. The 1:3 compound 5 has a more complicated structure, related to that of alkali metal alkynyl magnesates.
Ein Dimer von Ferroceno[1,2]cyclohexen-1-on-3 / A Dimer of Ferroceno[1,2]cyclohexen-1-one-3
Authors: Brunner Henri , Muschiol Manfred , Nuber Bernhard 
Published: February 2015

Abstract
A new by-product in the synthesis of ferroceno[1,2]cyclohexen-1-one-3 (1) is the dimer 2, which has been characterized by an X-ray analy­sis. Molecular structure of 2: Space group C 2h/6, C2/c, (15). Unit cell (Å): a = 42.54(3); b = 10.062(6); c = 22,04(1); monoclin; Z = 8.
Er2Au2Sn and other Ternary Rare Earth Metal Gold Stannides with Ordered Zr3Al2-Type Structure
Authors: Pöttgen Rainer 
Published: February 2015

Abstract
The ternary stannides RE2Au2Sn (RE = Y, Dy, Ho, Er, Tm, Lu) were prepared by arcmelting of the elemental components and subsequent annealing at 800 °C. The structure of Er2Au2Sn (single crystal, X-ray, P42/mnm, Z = 4, a = 778.2(2) pm, c = 739.6(3) pm, V = 0.4479 nm3 and R = 0.026) is described as the ternary ordered version of the Zr3Al2-type structure, a superstructure of the U3Si2-type. It consists of two-dimensionally infinite layers (Au2Sn)n which are separated by the erbium atoms. The structure is built up from slightly distorted [SnEr8) square prisms and [AuEr6] trigonal prisms which are condensed in all three directions. These fragments are derived from the well known AlB2 and CsCl-type structures.
Synthese und Kristallstruktur von NaMgl,64Cu0,36V3O10/ Synthesis and Crystal Structure of NaMgl,64Cu0,36V3O10
Authors: Martin F.-D. , Müller-Buschbaum Hk. 
Published: February 2015

Abstract
Single crystals of NaMg1.64Cu0.36V3O10 have been prepared by heating mixtures of Na2CO3, MgCO3, CuO and V2O5 above the melting point. The yellow crystals show triclinic symmetry, space group Ci
1-P1̅, a = 6.726(8), b = 6.743(7), c = 9.625(2) Å, α = 100.705(9), β = 104.57(1), γ = 101.700(9)°, Z = 2. NaMg1.64Cu0.36V3O10 represents a new structure type showing V3O10 groups, a statistical distribution of Mg2+ and Cu2+ on two point positions, and Na+ in an irregular coordination.
Die Kristallstrukturen von Magnesiumdibromid-Diglym-Addukten / Crystal Structures of Magnesium Dibromide Diglyme Adducts
Authors: Metzler Nils , Nöth Heinrich , Schmidt Martin , Treitl Andreas 
Published: February 2015

Abstract
(MgBr2·diglyme)2 (1) crystallized in low yield from an ether solution of the Grignard compound mesMgBr (mes = mesityl) on adding diglyme. It is more conveniently prepared from an ether solution of MgBr2 by addition of diglyme. The mixed solvate MgBr2·diglyme thf (2) crystallized from a diglyme/tetrahydrofuran solution of 1 after addition of ether. An X-ray structure determination of 1 reveals dimeric units containing hexacoordinated Mg atoms surrounded by three oxygen atoms and three bromide atoms, with each kind of atoms arranged in a meridional fashion. The two octahedral MgO3Br3 units share a common edge with two Br atoms. Compound 2 is a mononuclear complex with the Br atoms in cis-position. The diglyme ligand occupies meridional positions of a distorted MgBr2O4 octahedron.
Einkernige und oxoverbrückte zweikernige Fe(III)-Komplexe von N-Alkyl-N,N-bis(2-pyridylmethyl)aminen / Mononuclear and Oxo-Bridged Binuclear Fe(III) Complexes of N-Alkyl-N,N-bis(2-pyridylmethyl)amines
Authors: Dick Stefan , Weiss Armin , Wagner Ursel , Wagner Friedrich , Große Gerhard 
Published: February 2015

Abstract
Tridentate amines of the type N-alkyl-N,N -bis(2-pyridylmethyl)amine with alkyl = methyl L1, benzyl L2 and adamantyl L3 form mononuclear Fe(III) complexes LFeCl3. In the presence of various carboxylates binuclear μ-oxo-bis(μ-carboxylato) Fe(III) complexes [L2Fe2O(RCO2)2]2+ are formed. These compounds can be synthesized from mono-, bi-, tri- and tetranuclear iron complexes as starting materials.
The crystal structures of three mononuclear and four binuclear complexes show that the tridentate ligand is always facially coordinated to Fe. While in binuclear complexes of L1 and L2 the Namin-atom is trans to the oxo-bridge, in a complex of L3 a coordination with one Npyridin atom trans to that bridge is found. In all complexes the Fe-Namine distances increase with increasing space requirement of the alkyl substituent. The effects of different ligands trans to Namine and Npyridin are discussed.

57Fe Mößbauer spectra show that the electric field gradient at Fe vanishes in L1FeCl3 and L2FeCl3 despite non-cubic ligand spheres. For both mono- and binuclear complexes a correlation between isomer shift δ and Fe-N distances exists. The strong increase of Lamb-Mößbauer factors on cooling to 4,2 K and the Goldanski-Karyagin effect observed for some complexes can be explained by the displacement parameters of the Fe-atoms obtained by X -ray structure analysis.
Reaction between Yttrium Nitrate and 2,2':6',2"-Terpyridine (terpy) in MeCN: Preparation, Crystal Structures and Spectroscopic Characterization of [Y (NO3)3(terpy)(H2O )] and [Y(NO3)3(terpy)(H2O )] · terpy · 3 MeCN
Authors: Boudalis Athanassios K. , Nastopoulos Vassilios , Terzis Aris , Raptopoulou Catherine P. , Perlepes Spyros P. 
Published: February 2015

Abstract
The reaction of Y(NO3)3 · 5H2O and 2,2':6',2"-terpyridine (terpy) in MeCN leads to [Y(N03 )3(terpy)(H2O )] (1) and [Y(N03 )3(terpy)(H2O )] terpy-3MeCN (2) in good yields depending on the isolation conditions. The structures of both complexes were determined by single-crystal X-ray crystallography. The YIII atom in 1 is 9-coordinate and ligation is provided by one terdentate terpy molecule, two chelating nitrates, one monodentate nitrate and one terminal H2O molecule; the coordination polyhedron about the metal may be viewed as a tricapped trigonal prism. The YIII atom in 2 is 10-coordinate and its coordination sphere consists of three nitrogen atoms from the terdentate terpy, six oxygen atoms from the three chelating nitrates (one of them being “anisobidentate”) and one oxygen atom from a terminal H2O molecule; the polyhedron about the metal may be viewed as a distorted sphenocorona. The interstitial terpy is strongly hydrogen-bonded to the O atom of the coordinated H2O molecule to form [Y(NO3 )3(terpy)(H20)] ··· terpy pairs. The new complexes were characterized by IR and 1H NMR spectroscopies. The YIII/NO3
-/terpy chemistry is compared to the already well-developed LnIII/NO3
-/terpy chemistry (Ln = lanthanide).
Darstellung und Charakterisierung von Bis(trichlorsilyl)phenylamin und 2,2,4,4-TetrachIor-1,3-diphenyl-[ 1,3,2,4]diazadisiletidin / Preparation and Characterization of Bis(trichlorosilyl)phenylamine and 2,2,4,4-Tetrachloro-1,3-diphenyl-[ 1,3,2,4]diazadisiletidine
Authors: Bzik S. , Jansen M. 
Published: February 2015

Abstract
Bis(trichlorsilyl)phenylamine (1) and 2,2,4,4-tetrachlor-l,3-diphenyl-[l,3,2,4]diazadisiletid-ine (2) have been synthesized as potential precursors for the preparation of porous oxygen-free solids by the reaction of tetrachlorosilane with dilithiated aniline. Both compounds were characterized by crystal structure analysis. 1 crystallizes monoclinically, P2/n, a = 10.124(2), b = 12.701(2), c = 11.425(3) Å, β = 109.34(2)° and Z = 4 (R1 = 4.6%, wR2 = 11.6%, 1297 independent reflections). 2 crystallizes orthorhombically, Pbca, a = 11.42(1), b = 8.17(1), c = 17.05(1)Å, and Z = 4 (R1 = 3.7%, wR2 = 8.2%, 1923 independent reflections). Ammonolyses and polycondensation of 1 and 2 yield amorphous solids with low porosities.
Fluoreliminierung aus Graphitfluorid mit Magnesium / Defluorination of Graphite Fluoride Applying Magnesium Emst-Christian Koch
Authors: Koch Emst-Christian 
Published: February 2015

Abstract
Consolidated stoichiometric mixtures of graphite fluoride (1) and magnesium (2) upon igni­ tion under argon atmosphere (0,1 MPa) yield very high flame temperature of ~ 5600 K as determined by infrared emission spectroscopy. The combustion product was analysed by X-ray powder diffraction and revealed the presence of magnesium fluoride and graphite as well as structurally low ordered carbon. A possible reaction mechanism is discussed.
Synthesis and Coordination Chemistry of Novel Binucleating Macrocyclic Ligands with Amine-thioether and Amine-thiophenolate Donor Functions
Authors: Klingele Marco H. , Steinfeld Gunther , Kersting Berthold 
Published: February 2015

Abstract
The ability of the aromatic tetraaldehyde l,2-bis(4-tert-butyl-2,6-diformylphenylsulfanyl)-ethane (1) to function as a precursor in the preparation of binucleating hexaamine-dithiolate ligands has been investigated. Reductive amination of compound 1 with bis(aminoethyl)amine under medium-dilution conditions affords the macrobicyclic hexaamine-dithioether compound L1. Deprotection of the [1+2] condensation product gives the corresponding 24-membered hexa-amine-dithiophenol ligand H2L2. The formulation of L1 as a macrobicyclic amine-thioether was confirmed by an X-ray crystal structure determination of the tetranuclear nickel(II) complex of L1, [{(L1)Ni2Cl2}2(μ-Cl)3](BPh4) (2b). The formulation of the doubly deprotonated form (L2)2- of H2L2 as a 24-membered amine-thiophenolate ligand was confirmed by an X-ray crystal structure determination of the dinuclear cobalt(III) complex, [(L2)CoIII(μ-OH)](ClO4)2 · Cl (3). The preparation and the crystal structures of the new compounds are described.
Tetraberyllium-η4-oxo-hexa(arylcarboxylates)
Authors: Berger Raphael J. F. , Schmidt Michael A. , Jusélius Jonas , Sundholm Dage , Sirsch Peter , Schmidbaur Hubert 
Published: February 2015

Abstract
Tetraberyllium-oxo-hexabenzoate and -hexa(mesitylcarboxylate) were prepared from benzoic / mesitylcarboxylic acid and freshly precipitated beryllium hydroxide in a tetrahydrofuran / water two-phase system. The crystal structure of the benzoate was deter­ mined from Be4O(OCOPh)6(C6H6)3 , and that of the mesitylcarboxylate from the phase Be4O(OCOMes)6(CCl4). The two clusters have the μ4-oxo cage structure also detected for the acetate and nitrate complexes, and for the related hexacarbonato hexaanion. The high symmetry of the cluster allows the observation of 9Be and l7O signals in the solution NMR spectra.
The terminal atoms of the rigid carboxylate groups may be expected to lie at the vertices of large octahedra enclosing the cluster molecules. The axes of the six aryl groups would thus coincide with the axes of the cartesian coordinates with the μ4 oxygen atom at the origin. This disposition suggests a connectivity suitable for cubic lattices if p-difunctional arene-dicarb-oxylate anions are employed instead of aryl-monocarboxylate anions. However, the new results show that significant deviations of the OBe2O2C-Ar six-membered rings from planarity cause major deviations from octahedral symmetry and therefore no connectivity in cubic symmetry is to be expected.
Fragmentation of the Be4O(OCOR)6 clusters upon ionization in a mass spectrometer leads predominantly to cations [Be3O(OCOR)3]+ which can be assigned a planar, highly symmet­rical tricyclic core structure of D3h symmetry. Quantum chemical calculations confirm dis­ crete energy minima for these cations and show that their stability is largely due to the favourable arrangement of alternating charges of neighbouring core atoms. The high polar­ ity of Be-O bonds rules out any significant contributions from aromaticity. The reactions of Be(OH)2 with 4 -HS-C6H4 -COOH and HS(CH2)2COOH give the corresponding cluster com­ pounds Be4O(OCORSH)6, [R = C6H4 , (CH2)2] with six terminal mercapto functions.
Prmt5: a guardian of the germline protects future generations
Authors: Berrens Rebecca V , Reik Wolf 
Published: February 2015

Primordial germ cells (PGCs) are the embryonic precursors of the germ cell lineage that form sperm and egg cells. It is of great importance to preserve the germline from DNA damage and potentially from epimutations in order to ensure the survival of future generations. Recent research highlights the role of the protein arginine methyltransferase 5 (PRMT5) as an important player in DNA protection during germline development in the mouse (Kim et al, & Li et al, ).
Conserved RNA-Binding Proteins Required for Dendrite Morphogenesis inCaenorhabditis elegansSensory Neurons
Authors: Antonacci Simona , Forand Daniel , Wolf Margaret , Tyus Courtney , Barney Julia , Kellogg Leah , Simon Margo A , Kerr Genevieve , Wells Kristen L , Younes Serena , Mortimer Nathan T , Olesnicky Eugenia C , Killian Darrell J 
Published: February 2015

AbstractThe regulation of dendritic branching is critical for sensory reception, cell−cell communication within the nervous system, learning, memory, and behavior. Defects in dendrite morphology are associated with several neurologic disorders; thus, an understanding of the molecular mechanisms that govern dendrite morphogenesis is important. Recent investigations of dendrite morphogenesis have highlighted the importance of gene regulation at the posttranscriptional level. Because RNA-binding proteins mediate many posttranscriptional mechanisms, we decided to investigate the extent to which conserved RNA-binding proteins contribute to dendrite morphogenesis across phyla. Here we identify a core set of RNA-binding proteins that are important for dendrite morphogenesis in the PVD multidendritic sensory neuron in Caenorhabditis elegans. Homologs of each of these genes were previously identified as important in the Drosophila melanogaster dendritic arborization sensory neurons. Our results suggest that RNA processing, mRNA localization, mRNA stability, and translational control are all important mechanisms that contribute to dendrite morphogenesis, and we present a conserved set of RNA-binding proteins that regulate these processes in diverse animal species. Furthermore, homologs of these genes are expressed in the human brain, suggesting that these RNA-binding proteins are candidate regulators of dendrite development in humans.