Complexes of 18-crown-6 with oxonium ions derived from transition metal chlorides and hydrochloric acid: 18-crown-6.H3O+. FeCl4−, 18-crown-6.H3O+.InCl4−, (18-crown-6.H3O+)2.Pd2Cl62−

1989 ◽  
Vol 67 (1) ◽  
pp. 32-36 ◽  
Author(s):  
Robert Chênevert ◽  
Daniel Chamberland ◽  
Michel Simard ◽  
François Brisse

The macrocyclic polyether 18-crown-6 forms complexes with hydrates of strong acids derived from transition metal chlorides and hydrochloric acid. The following charged-component complexes have been isolated and characterized: 18-crown-6.H3O+.FeCl4−, 18-crown-6.H3O+.InCl4−, and (18-crown-6.H3O+)2.Pd2Cl62−. X-ray diffraction study of the palladium complex is reported. The oxonium ion is located at the center of the macrocyclic ether cavity and the symmetry of the ring is close to D3d. Keywords: 18-crown-6 complexes, oxonium ions, X-ray diffraction, crystal structure

2012 ◽  
Vol 620 ◽  
pp. 161-165
Author(s):  
Khatijah A. Yaacob ◽  
Jason D. Riley

The purpose of this research is to study the effect of synthesis temperature in order to produce anatase TiO2 nanoparticles (NPs) without using strong acids. In this research TiO2 nanoparticles was prepared by the hydrolysis and condensation of titanium (IV) isopropoxide in water at synthesis temperature of 0°C ± 0.1°C which produced anatase TiO2 crystallite size of 4.66 nm. XRD (X-ray diffraction) was used to analyse the crystal structure of the TiO2 and to calculate the crystallite size of the TiO2 nanoparticles. Transmission electron microscope (TEM) was also used to characterise the morphology of the TiO2 nanoparticles.


1978 ◽  
Vol 31 (1) ◽  
pp. 47 ◽  
Author(s):  
ES Kucharski ◽  
BW Skelton ◽  
AH White

The crystal structure of the title compound, [Co(terpy)(CO3)(OH)],4H2O, has been determined at 295 K by single-crystal X-ray diffraction and the use of diffractometer data, and refined by least squares to a residual of 0.075 for 1354 ?observed? reflections. Crystals are triclinic, Pī, a 11.407(6), b 10.566(6), c 8.445(4) Ǻ, α 100.21(5), β 107.35(5), γ 102.18(5)°, Z2. The structure of the molecule is unusual for a 1 : 1 transition metal/terpy complex in that the other ligating atoms are non-halide and the complex six-coordinate. The remaining three coordination positions about the metal are occupied by the bidentate carbonate (Co-O 1.918(9), 1.918(8) Ǻ) and the hydroxide ion (Co-O 1.894(10) Ǻ). The Co-N distances are appreciably shorter than those observed in other terpy systems (Co-N(central) 1.848(8); Co-N(outer) 1.946(9), 1.952(9) Ǻ).


1999 ◽  
Vol 23 (6) ◽  
pp. 388-389
Author(s):  
Li-Cheng Song ◽  
Wen-Qi Gao ◽  
Xiao-Ying Huang

Reaction of Cp(OC)2Cr=S = Cr(CO)2Cp with Fe3(CO)12 affords an encapsulated μ6-O octahedral Fe4Cr2 cluster complex Cp2Cr2Fe4(CO)12(μ6-O), whose crystal structure is determined by X-ray diffraction analysis.


1982 ◽  
Vol 35 (12) ◽  
pp. 2413 ◽  
Author(s):  
J Baldas ◽  
J Boas ◽  
J Bonnyman ◽  
MF Mackay ◽  
GA Williams

Tris[2-aminobenzenethiolato(2–)-S,N]technetium(VI), Tc(NHC6H4S)3, has been prepared by the reaction of ammonium pertechnetate with 2-aminobenzenethiol in 0.1 M hydrochloric acid solution at room temperature. The crystal structure of Tc(NHC6H4S)3 has been determined by single-crystal X-ray diffraction methods at 17�C. Crystals are orthorhombic, space group P212121, with a 10.696(2), b 11.363(1), c l5.220(2) �, and Z 4. Automatic diffractometry has provided significant Bragg intensities for 1413 independent reflections, and the structure of the correct enantiomorph has been refined by full-matrix least-squares methods to R 0.044. The compound, which is isostructural with the molybdenum analogue, consists of discrete molecules of Tc(NHC6H4S)3. The environment about the technetium atom closely approximates a trigonal-prismatic geometry. This is the first example where this geometry has been established with technetium. Differences in detail between the structures of TC(NHC6H4S)3 and its molybdenum analogue are discussed. In particular the S3N3 coordination polyhedron in TC(NHC6H4S)3is contracted and the distortions from ideal trigonal-prismatic geometry are less than in the molybdenum analogue.


Author(s):  
Süheyla Özbey ◽  
F. B. Kaynak ◽  
M. Toğrul ◽  
N. Demirel ◽  
H. Hoşgören

AbstractA new type of inclusion complex, S(–)-1 phenyl ethyl ammonium percholorate complex of R-(–)-2-ethyl - N - benzyl - 4, 7, 10, 13 - tetraoxa -1- azacyclopentadecane, has been prepared and studied by NMR, IR and single crystal X-ray diffraction techniques. The compound crystallizes in space group


1981 ◽  
Vol 46 (10) ◽  
pp. 2345-2353 ◽  
Author(s):  
Karel Baše ◽  
Bohumil Štíbr ◽  
Jiří Dolanský ◽  
Josef Duben

The 6-N(CH3)3-6-CB9H11 carbaborane reacts with sodium in liquid ammonia with the formation of 6-CB9H12- which was used as a starting compound for preparing the 4-CB8H14, 9-L-6-CB9H13 (L = (CH3)2S, CH3CN and P(C6H5)3), 1-(η5-C5H5)-1,2-FeCB9H10-, and 2,3-(η5-C5H5)2-2,31-Co2CB9H10- carboranes. The 4-CB8H14 compound was dehydrogenated at 623 K to give 4-(7)-CB8H12 carborane. Base degradation of 6-N(CH3)3-6-CB9H11 in methanol resulted in the formation of 3,4-μ-N(CH3)3CH-B5H10. The structure of all compounds was proposed on the basis of their 11B and 1H NMR spectra and X-ray diffraction was used in the case of the transition metal complexes.


2002 ◽  
Vol 67 (4) ◽  
pp. 479-489 ◽  
Author(s):  
Michal Hušák ◽  
Bohumil Kratochvíl ◽  
Ivana Císařová ◽  
Ladislav Cvak ◽  
Alexandr Jegorov ◽  
...  

Two new structures of semisynthetic ergot alkaloid terguride created by unusual number of symmetry-independent molecules were determined by X-ray diffraction methods at 150 K. Form A (monoclinic, P212121, Z = 12) contains three symmetry-independent terguride molecules and two molecules of water in the asymmetric part of the unit cell. The form CA (monoclinic, P21, Z = 8) is an anhydrate remarkable by the presence of four symmetry-independent molecules in the crystal structure. Conformations of twelve symmetry-independent molecules that were found in four already described terguride structures are compared with torsion angles obtained by ab initio quantum-mechanical calculations for the simplified model of N-cyclohexyl-N'-diethylurea.


2019 ◽  
Vol 74 (4) ◽  
pp. 357-363
Author(s):  
Daniela Vitzthum ◽  
Hubert Huppertz

AbstractThe mixed cation triel borate Ga4In4B15O33(OH)3 was synthesized in a Walker-type multianvil apparatus at high-pressure/high-temperature conditions of 12.5 GPa and 1300°C. Although the product could not be reproduced in further experiments, its crystal structure could be reliably determined via single-crystal X-ray diffraction data. Ga4In4B15O33(OH)3 crystallizes in the tetragonal space group I41/a (origin choice 2) with the lattice parameters a = 11.382(2), c = 15.244(2) Å, and V = 1974.9(4) Å3. The structure of the quaternary triel borate consists of a complex network of BO4 tetrahedra, edge-sharing InO6 octahedra in dinuclear units, and very dense edge-sharing GaO6 octahedra in tetranuclear units.


Sign in / Sign up

Export Citation Format

Share Document