scholarly journals Zur Darstellung und Kristallstruktur von β-NbO2 / Synthesis and Crystal Structure of β-NbO2

1982 ◽  
Vol 37 (11) ◽  
pp. 1361-1368 ◽  
Author(s):  
H.-J. Schweizer ◽  
Reginald Gruehn

By using chemical transport reactions with various transporting agents (HgCl2, NbCl5, Nb3O7Cl) a slightly substoiehiometric NbO2-phase, β-NbO2, was obtained from samples with O/Nb ∼ 1.5 (source; T > 1373 K) and with deposition temperatures > 1273 K (sink). The rango of composition of β-NbO2 was found to exist from NbO1.990 to NbO1.998.The structure of the tetragonal, column-shaped black crystals was determined by X-ray diffraction. It crystallizes tetragonally in the space group I41 with lattice constants a = 9.693(3) Å, c = 5.985(1) Å and Z = 10 formula units.The crystal structure of β-NbO2 is shown to be a deformed rutile type. As in α-NbO2 the Nb-atoms are grouped in pairs. However, both oxides are different with respect to their long-range order.

1985 ◽  
Vol 40 (3) ◽  
pp. 443-446 ◽  
Author(s):  
Udo Demant ◽  
Elke Conradi ◽  
Ulrich Müller ◽  
Kurt Dehnicke

[HC(NH2)2]3FeCl6 was obtained together with other products from the reaction of S4N4 with HCl in H2CCl2 in the presence of FeCl3. Its crystal structure was determined from X-ray diffraction data (473 independent observed reflexions, R = 0.047). Lattice constants: a = 961.6, c = 876.4 pm; tetragonal, space group P42/m, Z = 2. Of the two crystallographically independent formamidinium ions HC(NH2)2⊕, one exhibits positional disorder; the other one has C-N bond lengths of 128 pm. The FeCl63⊖ ions have symmetry C2h, but the deviation from Oh is small.


2007 ◽  
Vol 62 (1) ◽  
pp. 1-4 ◽  
Author(s):  
Nachiappan Arumugam ◽  
Eva-Maria Peters ◽  
Martin Jansen

A new potassium molybdenum oxide, K6Mo10O33, was synthesized by solid state reaction from the appropriate quantities of pre-dried MoO3 and K2MoO4, fired at around 650 °C for 2 d. The structure has been solved by using single crystal X-ray diffraction. The compound adopts the space group P1, with the lattice constants a = 7.7100(5), b = 11.9659(8), c = 17.1321(12) A° , α = 86.42 (10), β = 77.18(10), γ = 74.14(10)°. The structure is built up of infinite chains of edge-sharing MoO6 octahedra and groups of four MoO6 octahedra forming Mo4O17 units. These sub-units are connected together by common vertices.


1985 ◽  
Vol 40 (1) ◽  
pp. 13-18 ◽  
Author(s):  
Kay Jansen ◽  
Kurt Dehnicke ◽  
Dieter Fenske

The syntheses and IR spectra of the complexes [Mo2(O2C-Ph)4X2]2⊖ with X = N3, CI, Br and the counter ion PPh4⊕ are reported. The azido and the bromo complexes are obtained from a solution of [Mo2(O2CPh)4] with PPh4N3 in pyridine or by reaction with PPh4Br in CH2Br2, respectively. When (PPh4)2[Mo2(O2CPh)4(N3)2] is dissolved in CH2Cl2, nitrogen is evolved and the complex with X = CI is obtained. The crystal structure of (PPh4)2[Mo2(O2CPh)4Cl2] · 2CH2Cl2 was determined from X-ray diffraction data (5676 observed independent reflexions, R = 0.042). It crystallizes in the monoclinic space group P21/n with four formula units per unit cell; the lattice constants are a = 1549, b = 1400, c = 1648 pm, β = 94.6°. The centrosymmetric [Mo2(O2CPh)4Cl2]2⊖ ion has a rather short Mo-Mo bond of 213 pm, whereas the MoCl bonds are very long (288 pm)


1993 ◽  
Vol 48 (7) ◽  
pp. 1009-1012 ◽  
Author(s):  
Kurt Merzweiler ◽  
Harald Kraus

[{Cp(CO)2Fe}SnCl3] reacts with Na2Se in THF to form the compound [{Cp(CO)2Fe}3ClSn3Se4] 1. 1 crystallizes in the monoclinic space group P21/n with 4 formula units per unit cell. The lattice constants are α = 1435.2(7), b = 1124.4(4), c = 1972.7(12) pm, β = 94.59(4)°. According to the X-ray structure determination 1 contains a bicyclic Sn3Se4 framework.


2012 ◽  
Vol 86 (2) ◽  
Author(s):  
M. Maret ◽  
C. Brombacher ◽  
P. Matthes ◽  
D. Makarov ◽  
N. Boudet ◽  
...  

2011 ◽  
Vol 66 (11) ◽  
pp. 1087-1091 ◽  
Author(s):  
Olaf Reckeweg ◽  
Francis J. DiSalvo

Colorless and transparent single crystals of Ba2H3I were obtained by reacting Ba with dried and sublimed NH4I in a 4 : 1 molar ratio in silica-jacketed Nb ampoules at 1100 K for 13 h. The crystal structure of the title compound was determined and refined by means of single-crystal X-ray diffraction. Ba2H3I crystallizes in a stuffed anti-CdI2 structure isotypic to Sr2H3I in the space group P3̄m1 (no. 164) with the lattice parameters a = 451.86(12) and c = 811.84(23) pm. The structural results for Ba2H3I are consistent with bond lengths and coordination geometries of related binary and ternary hydrides


1990 ◽  
Vol 45 (8) ◽  
pp. 1193-1196 ◽  
Author(s):  
Klaus Brodersen ◽  
Axel Knörr

[Hg2(p-SC6H4NO2)]NO3 is formed by the reaction of p-nitrothiophenol with dimercury(I)-dinitrate in methanol. It crystallizes in the monoclinic space group P21/n with a = 1175.5(9) pm, b = 1079.8(8) pm, c = 876.2(8) pm, β = 110.74(4)° and Z = 4. The crystal structure has been determined by X-ray diffraction and refined to an R-value of 0.052. The results show that the compound exists as a chain structure of [—®S(C6H4NO2)— Hg— Hg—]n with nitrate ions connecting the chains.


1992 ◽  
Vol 47 (8) ◽  
pp. 1063-1066 ◽  
Author(s):  
Alfred-Dirk Bacher ◽  
Ulrich Müller

[Na(15-crown-5)]2S6 was obtained from Na2S4 und 15-crown-5 in acetonitrile. Its crystal structure was determined by X-ray diffraction with 2968 observed reflexions, R = 0.119. Crystal data: a = 861.4(9), b = 1006(1), c = 2097(1) pm, α = 89.7(1), β = 100.20(8), γ = 114.6(1)°, Ζ = 2, space group Ρ 1̄. The chain-like S62- ion has transoid conformations, each of its terminal atoms is in contact with one Na+ ion which in turn is coordinated with one crown ether molecule.


2015 ◽  
Vol 2015 ◽  
pp. 1-5
Author(s):  
Shuang Gao ◽  
Hai-Tao Qu ◽  
Fei Ye ◽  
Ying Fu

A new compound,N-dichloroacetyl-3,4-dihydro-3-methyl-6-chloro-2H-1,4-benzoxazine, was synthesized and characterized. The crystal structure of the title compound (C11H10Cl3NO2,Mr=294.55) has been determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space groupP21/c, witha=6.7619(14),b=24.866(5),c=9.737(3) Å,α=90.00,β=130.982(18),γ=90.00°,V=1235.9(5) Å3,Z=4,Dx=1.583 Mg/cm3,λ(Mo  Ka)=0.71073 Å,F(000)=600,μ=0.729 mm−1,R=0.0476, andwR=0.1274for 2217 reflections withI>2σ(I).


Sign in / Sign up

Export Citation Format

Share Document