Experimental and Theoretical Study on the Structure of Nitramide H2NNO2

2002 ◽  
Vol 57 (2) ◽  
pp. 151-156 ◽  
Author(s):  
Angelika Häußler ◽  
Thomas M. Klapötke ◽  
Holger Piotrowski
Keyword(s):  
Crystal Structure ◽  
Bond Length ◽  
Gas Phase ◽  
Bond Order ◽  
Theoretical Study ◽  
Crystal Structure Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Planar Conformation ◽  
Multinuclear Nmr Spectroscopy

Nitramide was investigated by multinuclear NMR spectroscopy, X-ray-diffraction and computational methods. The crystal structure analysis at various temperatures reveals a planar conformation of the molecule with a N-N bond length corresponding to a bond order between one and two. Hydrogen bonds connect the nitramide molecules side-on and end-on. This leads to the formation of layers in the crystal. Calculations were performed to explain the shorter N-N bond length in the crystal compared to the gas phase. The nitramide trimer is used as a model.

Nitrido-und Oxochlorokomplexe des Vanadiums(V); die Kristallstruktur von AsPh4 [V0C14] Nitrido and Oxochloro Complexes of Vanadium(V); the Crystal Structure of AsPh4[VOCl4]

1980 ◽  
Vol 35 (5) ◽  
pp. 522-525 ◽  
Author(s):  
Gisela Beindorf ◽  
Joachim Strähle ◽  
Wolfgang Liebelt ◽  
Kurt Dehnicke
Keyword(s):  
Crystal Structure ◽  
Ir Spectra ◽  
Bond Length ◽  
Bond Angle ◽  
Unit Cell ◽  
X Ray Diffraction ◽  
Linear Arrangement ◽  
Space Group ◽  
X Ray ◽  
Complex Anions

The complexes AsPh4[Cl4V = N-Cl] and AsPh4[VOCl4] are prepared by the reaction of AsPh4Cl with Cl3VNCl and VOCl3, respectively. The IR spectra indicate C4v symmetry for the complex anions with multiple VN and VO bonds and a linear arrangement for the VNCl-group. AsPh4[VOCl4] crystallizes in the tetragonal space group P4/n with two formula units in the unit cell. The crystal structure was solved by X-ray diffraction methods (R = 0,062, 1096 observed, independent reflexions). The structure consists of AsPh4+ cations and [VOCl4]- anions with symmetry C4v. The extremely short VO bond length corresponds with a VO triple; its steric requirements cause the relatively large bond angle OVCl of 103.4°.

scholarly journals E. S. Fedorov Promoting the Russian-German Scientific Interrelationship

Minerals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 181 ◽  
Author(s):  
Peter Paufler ◽  
Stanislav K. Filatov
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
Structure Analysis ◽  
Crystalline State ◽  
Crystal Structure Analysis ◽  
Present Knowledge ◽  
Personal Contact ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Impact

At the dawn of crystal structure analysis, the close personal contact between researchers in Russia and Germany, well documented in the “Zeitschrift für Krystallographie und Mineralogie”, contributed significantly to the evolution of our present knowledge of the crystalline state. The impact of the Russian crystallographer E. S. Fedorov upon German scientists such as A. Schoenflies and P. Groth and the effect of these contacts for Fedorov are highlighted hundred years after the death of the latter. A creative exchange of ideas paved the way for the analysis of crystal structures with the aid of X-ray diffraction.

scholarly journals The characterisation and X-ray crystal structure of pentabromodiselenium hexafluoroarsenate, Se2Br5AsF6; some thermodynamic considerations and the nonexistence of Se2I5AsF6

1987 ◽  
Vol 65 (7) ◽  
pp. 1584-1593 ◽  
Author(s):  
Michael P. Murchie ◽  
Jack Passmore ◽  
Peter S. White
Keyword(s):  
Crystal Structure ◽  
Bond Order ◽  
Room Temperature ◽  
Bromine Atom ◽  
Elemental Selenium ◽  
Analogous Reaction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Final Agreement ◽  
Anion Interaction

The crystal structure of Se2Br5AsF6 was determined by low-temperature X-ray diffraction methods. Single crystals of Se2Br5AsF6 are rhombohedral, space group R3 with a = 13.367(4) Å, c = 19.000(6) Å, V = 2940 Å3, and Z = 9. The structure was refined to final agreement indices of R = 0.087, Rw = 0.093 for 604 observed (I > 3σ(I)) reflections and 71 parameters. The structure consists of essentially discrete Se2Br5+ cations and AsF6− anions with some cation–anion interaction. The Se2Br5+ cation, of essentially C2h symmetry contains two trans SeBr2 units, linked by a bridging bromine atom. The two terminal selenium–bromine bond distances are 2.291(7) and 2.268(6) Å, of bond order 1, and the angle between them is 100.0(3)°. The bridging bromine atom lies at the inversion centre of the Se2Br5+ cation, with an Se—Br distance of 2.582(3) Å, corresponding to a bond order of about 0.5. The two angles between the bridging Se—Br and terminal Se—Br bonds are 97.4(1)° and 98.9(2)°. Se2Br5AsF6 decomposes slowly at room temperature and rapidly at 100 °C leading to the formation of SeBr3AsF6, SeBr4, and elemental selenium. It reacts with Br2 to give SeBr3AsF6 and SeBr4. Se2Br5AsF6 is prepared by the reaction of Se4(AsF6)2 and the appropriate quantity of Br2. The analogous reaction with I2 leads to I2SeSeSeSeI2(AsF6)2 and not Se2I5AsF6. These differences have been accounted for on the basis of estimates of the appropriate bond and crystal lattice energies. The 77Se nmr of SeBr3+ and Se2Br5+ in SO2 solution, and the Raman spectrum of SeBr4 are reported.

Crystal-to-Crystal Diastereoselective Transformation of 2,4,6-Triisopropyl-4'-(S)-phenylalaninocarbonylbenzophenone Methyl Ester

1998 ◽  
Vol 54 (6) ◽  
pp. 907-911 ◽  
Author(s):  
H. Hosomi ◽  
Y. Ito ◽  
S. Ohba
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Methyl Ester ◽  
Absolute Configuration ◽  
Crystal Structure Analysis ◽  
X Ray Diffraction ◽  
Pass Filter ◽  
X Ray ◽  
Ultra High Pressure ◽  
Phenylalanine Methyl Ester

Dissymmetry of the photoproduct was induced by using a chiral substituent, (S)-methylphenylalanine, in the title compound {N-4-(2,4,6-triisopropylbenzoyl)benzoyl]-(S)-phenylalanine methyl ester (I)}. On irradiation with light from a 250 W ultra-high-pressure Hg lamp for 7 h through a long-pass filter, the photoreaction in a crystal was 100% complete without the loss of crystallinity. The crystal structures (I), before, and (II) {N-[4-(7-hydroxy-3,5-diisopropyl-8,8-dimethylbicyclo[4.2.0]octa-1,3,5-trien-7-yl)benzoyl]-(S)-phenylalanine methyl ester}, after photocyclization, have been determined by X-ray diffraction. For comparison, a crystal structure analysis has also been carried out for the photoproduct (III) of the 3′-COOMe derivative after recrystallization {methyl 3-(7-hydroxy-3,5-diisopropyl-8,8-dimethylbicyclo[4.2.0]octa-1,3,5-trien-7-yl)benzoate}. The dihedral angle between the central carbonyl plane and the triisopropylphenyl ring deviates from 90° by 10 (1)° in (I), which makes an imbalance in the intramolecular O(carbonyl)...H(methine) distances of the isopropyl groups at positions 2 and 6. The crystal structure of (II) indicates that the nearer methine H was predominantly abstracted by the carbonyl O atom in the reaction. The absolute configuration around the asymmetric C atom in the cyclobutenol ring of the product is S.

A fourfold interpenetrating diamond-like three-dimensional zinc(II) coordination polymer: synthesis, crystal structure and physical properties

2019 ◽  
Vol 75 (5) ◽  
pp. 504-507 ◽  
Author(s):  
Hui-Ru Chen
Keyword(s):  
Crystal Structure ◽  
Room Temperature ◽  
Three Dimensional ◽  
Fluorescence Emission ◽  
Crystal Structure Analysis ◽  
The Novel ◽  
X Ray Diffraction ◽  
Metal Compounds ◽  
X Ray ◽  
Coordination Framework

Excellent fluorescence properties are exhibited by d 10 metal compounds. The novel three-dimensional ZnII coordination framework, poly[[{μ2-bis[4-(2-methyl-1H-imidazol-1-yl)phenyl] ether-κ2 N 3:N 3′}(μ2-furan-2,5-dicarboxylato-κ2 O 2:O 5)zinc(II)] 1.76-hydrate], {[Zn(C6H2O5)(C20H18N4O)]·1.76H2O} n , has been prepared and characterized using IR spectroscopy, elemental analysis and single-crystal X-ray diffraction. The crystal structure analysis revealed that the compound exhibits a novel fourfold interpenetrating diamond-like network. This polymer also displays a strong fluorescence emission in the solid state at room temperature.

scholarly journals A Salt Metathesis Route To Ruthenium Carbene Complex Isomers With Pyridine Dicarboxamide-Derived Chelate Pincer Ligands

2007 ◽  
Vol 62 (6) ◽  
pp. 783-790 ◽  
Author(s):  
Carolin Wallenhorst ◽  
Kirill V. Axenov ◽  
Joseph S. M. Samec ◽  
Roland Fröhlich ◽  
Gerhard Erker
Keyword(s):  
Crystal Structure ◽  
Single Crystals ◽  
Structure Analysis ◽  
Crystal Structure Analysis ◽  
Pincer Ligands ◽  
X Ray Diffraction ◽  
X Ray ◽  
Carbene Complex ◽  
Related Complex

Reaction of the doubly deprotonated pyridine 2,6-dicarboxamido ligand (1) with (PCy3)2Cl2 Ru=CHPh (3a) in THF gave a mixture of (lig)(PCy3)Ru=CHPh isomers (4). The pentane soluble N,N,O-4 isomer was isolated by extraction and characterized by X-ray diffraction. The O,N, O-4 isomer was identified in the residue. Single crystals of the closely related complex (lig)(NHC) Ru=CHPh, O,N,O-5, were obtained from the reaction of 1 with (NHC)(PCy3)Cl2Ru=CHPh (3b) and used for the X-ray crystal structure analysis of the system

Structure and Bonding of Bromoantimonate (III) Complexes with Unusual Valency by Means of NQR and Powder X-Ray Diffraction

1994 ◽  
Vol 49 (1-2) ◽  
pp. 185-192 ◽  
Author(s):  
Tsutomu Okuda ◽  
Yoshihiro Kinoshita ◽  
Hiromitsu Terao ◽  
Koji Yamada
Keyword(s):  
Crystal Structure ◽  
Phase Transition ◽  
Bond Length ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structure And Bonding ◽  
Bond Character

Abstract NQR and powder X-ray diffraction were observed for several bromoantimonate (III) complexes which contain CnH2n+1NH3 (n = 1 -3) or (CnH2n+1)2NH2(n = 1 -4) as a cation. The bond character, anion structure, crystal structure, and phase transition are discussed on the basis of the three-center-four-electron bond. A good correlation was found between the halogen NQR frequency and the Sb-X bond length.

Hydrothermal Synthesis and Structure Characterization of a Bi-Capped Keggin Heteropoly Molybdovanadated Derivative

2014 ◽  
Vol 1004-1005 ◽  
pp. 542-545
Author(s):  
Ya Bing Liu ◽  
Li Guang Xiao
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonding ◽  
Building Blocks ◽  
Crystal Structure Analysis ◽  
Structure Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hydrogen Bonding Interactions ◽  
Supramolecular Networks

A new bi-capped Keggin heteropoly molybdovanadated derivative, [Co (en)3]2[SiMo8V6O42]∙6H2O (1) (en = ethylendiamine) has been hydrothermally synthesized and structurally characterized by the elemental analysis, IR, XPS and single crystal X-ray diffraction. The crystal structure analysis reveals that compound 1 consists of [Co (en)3]2+transition metal coordination fragment and the [SiMo8V6O42]4-building blocks, which are linked together via hydrogen-bonding interactions to form a new 3-D supramolecular networks.

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