Polyamine ligands. III. Five-coordinate complexes with the quinquedentate N,N,N'-Tris[2-(2'-pyridyl)ethylethylenediamine

1971 ◽  
Vol 24 (3) ◽  
pp. 501 ◽  
Author(s):  
AT Phillip ◽  
W Mazurek ◽  
AT Casey
Keyword(s):  
Magnetic Susceptibility ◽  
Diffraction Analysis ◽  
Electronic Absorption ◽  
Metal Ion ◽  
Electronic Absorption Spectra ◽  
Ligand Field ◽  
Field Calculation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Free Amine

The quinquedentate ligand, N,N,N?-tris[2-(2?- pyridyl)ethyl]ethylenediamine (tpen), has been synthesized from ethylenediamine and 2-vinylpyridine. The free amine tpen is thermally unstable, but readily forms chemically stable metal complexes of the composition [M(tpen)](ClO4)2 (M = Cu, Ni, Zn) and [Co(tpen)O2Co(tpen)]- (ClO4)4. In each of these compounds, the amine tpen is bonded to the metal ion through all five of its nitrogen atoms, as indicated by infrared and electronic absorption spectra and magnetic susceptibility measurements. The compound [Ni(tpen)](ClO4)2 shows four d-d transitions whose energies correspond closely to the values predicted from a ligand field calculation for a square pyramidal NiN5 chromophore. This structure has been confirmed by X-ray diffraction analysis. These complexes of tpen are the first reported quinquedentate pentaamine chelate structures of copper(II), nickel(II), and zinc(II).

Application of Gel Technology in Preparation of High-Tc Perovskite Superconductors

1987 ◽  
Vol 99 ◽  
Author(s):  
R. S. Liu ◽  
G. C. Lin ◽  
H. M. Sung ◽  
Y. C. Chen ◽  
O. C. C. Lin
Keyword(s):  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Diffraction Analysis ◽  
Dicarboxylic Acids ◽  
X Ray Diffraction ◽  
Chemical Homogeneity ◽  
High Tc ◽  
X Ray ◽  
Electrical And Magnetic Properties ◽  
High Degree

ABSTRACTLa-Ba-Cu-O and Y-Ba-Cu-O superconducting systems have been successfully prepared by gel techniques with high degree of chemical homogeneity. The precursor gel was synthesized from mixture of the corresponding metallic nitrates and di-carboxylic acids. The sintered oxides prepared from the different dicarboxylic acids were all Tc = 90K perovskite superconductors. However differences in electrical and magnetic properties were also observed. Effects due to the different acids elucidated by magnetic susceptibility measurements and X-ray diffraction analysis will be discussed.

Characterization of the adducts of bis(O-isoamyldithiocarbonato) nickel(II) with heterocyclic amines and X-ray structure of bis(O-isoamyldithiocarbonato)-bis(3-bromopyridine)nickel(II)

2016 ◽  
Vol 57 (8) ◽  
pp. 1688
Keyword(s):  
Magnetic Susceptibility ◽  
Spectral Data ◽  
Metal Ion ◽  
Diffraction Method ◽  
Bidentate Ligand ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cell Parameters ◽  
Infrared Spectral ◽  
Substituted Pyridines

A series of six-coordinated Ni(II) complexes, with the general formula Ni(Xan)L2 (where Xan = isoamyldithiocarbonato and L = 2-bromopyridine, 3-bromopyridine, 4-acetylpyridine, 3-hydroxypyridine and 2-methoxypyridine) are synthesized and characterized by the elemental analysis and various physicochemical techniques such as magnetic susceptibility and conductivity measurements, UV-visible and infrared spectral data. Based on the electronic spectra and magnetic susceptibility measurements, an octahedral geometry is proposed for all the complexes. IR spectral data show that in all these complexes substituted pyridines coordinate to the metal ion through nitrogen atoms occupying the fifth and sixth axial positions, whereas O-alkyldithiocarbonate acts as a monoanion bidentate ligand and occupies the planar positions of octahedral structures. The structure of the adduct with 3-bromopyridine is elucidated by the single crystal X-ray diffraction method. The complex crystallizes in the triclinic space group P-1 with unit cell parameters a = 6.5855(4) Å, b = 9.4984(6) Å, c = 12.4518(8) Å, α = 87.944(5)°, β = 78.843(5)°, γ = 77.794(5)°. The crystal structure of the molecule is stabilized by intermolecular C—H…S and C—H…π interactions.

Electronic Structure of 2,6-Bis{.N-(2-hydroxyphenyl)immoinethyl}-4-methylphenol

1999 ◽  
Vol 54 (7) ◽  
pp. 929-939 ◽  
Author(s):  
Miki Hasegawa ◽  
Yasunori Yamada ◽  
Ken-ichi Kumagai ◽  
Toshihiko Hoshi
Keyword(s):  
Diffraction Analysis ◽  
Electronic Absorption ◽  
Nmr Spectra ◽  
X Ray Diffraction ◽  
Mo Calculations ◽  
Absorption Bands ◽  
Polar Solvents ◽  
Additional Band ◽  
X Ray ◽  
H Nmr

The electronic and molecular structure of 2,6-bis{N-(2-hydroxyphenyl)iminomethyl}-4- methylphenol (hpimp) is clarified from the measurements of electronic absorption and 1H NMR spectra in various solvents and an X-ray diffraction analysis, together with MO calculations. Electronic absorption bands of hpimp are at 422, 397.9, 359, 341, 294.3, 265.8, and 224 nm in the non-polar solvent cyclohexane. In polar solvents, such as methanol, an additional band which is assigned to a partly formed keto-amine hpimp, is observed at 499 nm. From the 1H NMR spectra it is seen that hpimp exists in the enol-imine form in non-polar solvents, and as an equilibrium mixture of enol-imine and keto-amine forms in polar solvents. Each electronic absorption band of solid hpimp in a KBr disk is broadened compared with the solution state, and an additional band, again assigned to the keto-amine form, appears around 499 nm. An X-ray diffraction analysis shows that hpimp assumes a keto-amine structure in the solid state, and forms a column structure along the c-axis. MO calculations suggest that the enol-imine hpimp has a twist structure around the two C−C single bonds, the twist angle being 100° to 120°.

Bis/tris[octakis(hexylthio)phthalocyaninato] europium(III) complexes: structure, spectroscopic, and electrochemical properties

2013 ◽  
Vol 17 (08n09) ◽  
pp. 673-681 ◽  
Author(s):  
Chunhua Huang ◽  
Yi Zhang ◽  
Junshan Sun ◽  
Yongzhong Bian ◽  
Dennis P. Arnold
Keyword(s):  
Cyclic Voltammetry ◽  
Ir Spectroscopy ◽  
Diffraction Analysis ◽  
Electrochemical Properties ◽  
Electronic Absorption ◽  
Elemental Analysis ◽  
Molecular Structures ◽  
Spectroscopic Methods ◽  
X Ray Diffraction ◽  
X Ray

Bis/tris(phthalocyaninato) europium double- and triple-decker complexes Eu [ Pc (β- SC 6 H 13)8]2 (1) and Eu 2[ Pc (β- SC 6 H 13)8]3 (2) [ Pc (β- SC 6 H 13)8 = 2, 3, 9, 10, 16, 17, 23, 24-octakis(hexylthio)phthalocyaninate] have been synthesized and characterized by a series of spectroscopic methods including mass, NMR, electronic absorption and IR spectroscopy in addition to elemental analysis. Their molecular structures have been determined by single crystal X-ray diffraction analysis and electrochemical properties studied by cyclic voltammetry.

Studies of β-Diketone Complexes of Rhenium. I. Trispentane-2,4-dionatorhenium(III) and Tris(1,1,1,5,5,5-hexafluoropentane-2,4-dionato)rhenium(III)

1972 ◽  
Vol 50 (1) ◽  
pp. 8-17 ◽  
Author(s):  
W. D. Courrier ◽  
W. Forster ◽  
C. J. L. Lock ◽  
G. Turner
Keyword(s):  
Crystal Structure ◽  
Mass Spectrometry ◽  
Magnetic Susceptibility ◽  
Infrared Spectroscopy ◽  
Physical Properties ◽  
Ligand Field ◽  
X Ray Diffraction ◽  
Rhenium Atom ◽  
X Ray ◽  
Monoclinic Cell

Pure samples2 of Re(hfac)3 and Re(acac)3 have been prepared and their physical properties studied by ultraviolet–visible and infrared spectroscopy, mass spectrometry, magnetic susceptibility measurements, and X-ray diffraction. The compounds are monomeric and the physical properties may be explained if the rhenium atom sits in an essentially octahedral ligand field. Re(hfac)3 has a hexagonal unit cell and the acetyl-acetone complex adopts the monoclinic cell of the α-form of the three typical crystal structure types which Astbury (1) observed for trispentane-2,4-dionatometal(III) compounds. The properties observed for trispentane-2,4-dionatorhenium(III) differ from those reported previously (2, 3). The difficulties experienced in obtaining pure Re(C5H7O2)3 were caused by the ease with which the material is oxidized.

Molecular geometry of (E)- and (Z)-9-(β-Styryl)anthracenes

1984 ◽  
Vol 37 (11) ◽  
pp. 2215 ◽  
Author(s):  
H Becker ◽  
VA Patrick ◽  
AH White
Keyword(s):  
Fine Structure ◽  
Double Bond ◽  
Electronic Absorption ◽  
Electronic Absorption Spectra ◽  
Molecular Geometry ◽  
Diels Alder ◽  
Molecular Structures ◽  
X Ray Diffraction ◽  
X Ray ◽  
Limited Mobility

The molecular structures of (Z)-9-(8-styryl)anthracene, C22H16,(I),(E)-9-(P-styryl)anthracene, (2), and the photo-Diels-Alder dimer of 9-phenylethynylanthracene, C44H28, (3), containing a (Z)-9- (β-styryl) anthracene moiety of limited mobility have been determined by X-ray diffraction. Crystals of (1) are monoclinic, P21/c, a 5.507(4), b 13.050(7), c 21.425(10)�, β 95.73(5)�, Z 4; R was 0.047 for No 1604 independent 'observed' reflections. Crystals of (2) are monoclinic, P21/n, a 11.77(1), b 24.35(2), c 5.503(5) �, β 107.38(7)�, Z 4; R 0.050 for No 1100. Crystals of (3) are monoclinic, P21/c, a 10.719(7), b 18.627(8), c 15.509(8) �, β 101.10(5)�, Z 4; R 0.070 for No 1055. Increase in angle between the plane of the anthracene and the plane of the ethylenic double bond (78.4, 65.5, 81.9� respectively) is reflected in the electronic absorption spectra by an enhancement of the fine structure typical of the anthracene chromophore.

Some substituted urea and thiourea complexes of Co(II), Mn(II), and Cr(III)

1969 ◽  
Vol 47 (12) ◽  
pp. 2275-2282 ◽  
Author(s):  
Pakinam Askalani ◽  
R. A. Bailey
Keyword(s):  
Magnetic Susceptibility ◽  
Ligand Field ◽  
X Ray Diffraction ◽  
Visible Spectroscopy ◽  
X Ray ◽  
Ligand Field Parameters ◽  
Substituted Urea

Complexes of Co(II), Mn(II), and Cr(III) with N-butylurea, N-methylthiourea, and N,N′-dimethylthiourea, and Cl−, Br−, NO3−, and ClO4− anions were prepared and characterized using infrared and visible spectroscopy, and magnetic susceptibility. The urea is bonded through oxygen, and the thioureas through sulfur in all cases. The Co–N-butylurea compounds are octahedral, mostly with CoL6X2 stoichiometries, but some compounds involving coordinated anions and possibly bridging butylurea ligands were found. The Co–thioureas are tetrahedral. Octahedral Cr(III) compounds of the type CrL3X3 and CrL6(ClO4)3 were prepared, and the CrS6 chromophore characterized. Mn(II)–butylureas are octahedral, while the thioureas show MnL6X2 and MnL4X2 stoichiometries. X-ray diffraction established some of the latter to be isostructural with the analogous tetrahedral Co(II) compounds. Ligand field parameters Dq and B have been evaluated for the Co(II) and Cr(III) compounds.

A 3D mixed-valence Cu(I)/Cu(II) coordination polymer constructed by 2-(2-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline and 1,3-benzenedicarboxylate

2015 ◽  
Vol 70 (12) ◽  
pp. 857-861
Author(s):  
Zhi-Guo Kong ◽  
Sheng-Nan Guo ◽  
Bo Sun ◽  
Seik Weng Ng
Keyword(s):  
Magnetic Susceptibility ◽  
Coordination Polymer ◽  
Diffraction Analysis ◽  
Mixed Valence ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
Hydrothermal Conditions ◽  
X Ray ◽  
Benzenedicarboxylic Acid

AbstractA mixed-valence Cu(I)/Cu(II) coordination polymer, namely, [Cu2(L)(1,3-BDC)]n (1), has been synthesized under hydrothermal conditions (HL = 2-(2-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline and 1,3-H2BDC = 1,3-benzenedicarboxylic acid). Its structure has been determined by single crystal X-ray diffraction analysis and powder X-ray diffraction. The crystals are the monoclinic space group P21/c with a = 10.686(4), b = 17.376(8), c = 11.759(4) Å, β = 92.072(14)°, C27H14Cu2FN4O4, Mr = 604.50, V = 2182.1(15) Å3, Z = 4, Dcalcd. = 1.84 g cm–3, R = 0.0588 and wR = 0.1202 (all data). In complex 1, the mixed-valence Cu(I)/Cu(II) atoms are linked by L and 1,3-BDC to give a rare 3D (3,3,4)-connected (4.7.9)(7.8.9)(4.7.8.93) framework. The temperature-dependent magnetic susceptibility of 1 was investigated in the temperature range of 2–300 K.

Crystallization of Proteins, Nucleic Acids, and Viruses for X‐ray Diffraction Analysis

2003 ◽  
Author(s):  
Alexander McPherson ◽  
Robert Cudney ◽  
Sam Patel
Keyword(s):  
Nucleic Acids ◽  
Diffraction Analysis ◽  
X Ray Diffraction ◽  
X Ray
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