Antiferromagnetic super exchange and spectral studies on dimeric 8-quinolinolato complexes of copper(II) imides

1985 ◽  
Vol 63 (11) ◽  
pp. 3027-3030 ◽  
Author(s):  
C. L. Sharma ◽  
V. Mishra

The complexes of the type [Cu(Q)(P)]2 and [Cu(Q)(S)]2 where HQ = 8-hydroxyquinoline and P and S are deprotonated phthalimide and succinimide, respectively, were prepared and characterized on the basis of molecular mass determination, elemental analysis. X-ray diffraction, ir, electronic spectra, conductance, thermal analysis, and magnetic measurements. They were of tetrahedrally distorted square planar structure. The susceptibility data at different temperatures were fitted to the Bleaney–Bowers equation which indicated medium antiferromagnetic super exchange interaction within one dimeric unit. The values of exchange integral and g were found to be −136 cm−1 and 2.18, respectively, for the phthalimide complex and −128 cm−1 and 2.16, respectively, for the succinimide complex.

2019 ◽  
Vol 74 (6) ◽  
pp. 485-489
Author(s):  
Yuan Huang ◽  
Xiu-feng Yu ◽  
Zhen Rong ◽  
Yi-chun Ai ◽  
Kun Qian ◽  
...  

AbstractA new complex [Pr3NH]+ [Mn(dca)3]− · H2O (dicyanamide = dca−) was synthesized, in which the Mn2+ cations are bridged by end-to-end dca anions to form three-dimensional [Mn(dca)3]nn− networks and tripropylammonium cations reside in the cavities of these networks. The complex has been characterized by single-crystal X-ray diffraction, infrared spectroscopy, elemental analysis, and magnetic measurements. Magnetic susceptibility data indicate ferromagnetic interactions among the MnII ions.


2000 ◽  
Vol 55 (9) ◽  
pp. 796-802 ◽  
Author(s):  
H. Kara ◽  
Y. Elerman ◽  
K. Prout

Preparation and magnetic properties of a 3,5-dimethylpyrazolate bridged binuclear copper(II) complex [Cu2(L)(3 ,5 -pyz)] (L = 1,3-Bis(2-Hydroxy-5-Chlorosalicylideneamino)propan- 2-ol) is reported. The crystal structure determined by X-ray diffraction methods. (C22H20N4O3CI2CU2), triclinic, space group P1̄, a = 9.622(3), b = 10.921(2), c = 11.420(3) Å, α = 100.73(2), β = 94.04(2), Υ = 108.08(2)°, V = 1110.2(5) Å3, Z = 2. Two copper(II) ions in a square-planar coordination are bridged via alkoxide oxygen and 3,5-dimethyl pyrozolate nitrogen atoms to form a dinuclear unit. The metal coordination sphere is four-coordinate, planar with an N2O2 donor set. The dihedral angle between the two coordination planes is 166.83°. There are significant intermolecular interactions between neighbouring binuclear entities. The shortest intermolecular Cu (1) ... Cu(1)i distance is 3.383(1) Å and the Cu(1) - O ( 1)i distance is 2.666(3) Å (i = 1 -x, -y, 1 - z). The variable-temperature magnetic susceptibility measurement for a powdered sample of the complex was carried out in the temperature range 5 - 350 K and analysed to obtain values of the parameter J in the exchange Hamiltonian ℋ = -2JScu Scu; 2J = -164 cm-1. The magnetic moment at 300 K is about 2.42 μB, and 0.22 μB at 5 K. The weak antiferromagnetism of the present complex is reasonably explained in terms of the orbital countercomplementary effect based on Hoffmann's theory for super-exchange interaction


2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Jonnie N. Asegbeloyin ◽  
Oguejiofo T. Ujam ◽  
Emmanuel C. Okafor ◽  
Ilknur Babahan ◽  
Esin Poyrazoglu Coban ◽  
...  

Reaction of 1-phenyl-3-methyl-4-benzoyl-pyrazol-5-one and benzoyl hydrazide in refluxing ethanol gaveN′-[(Z)-(3-methyl-5-oxo-1-phenyl-1,5-dihydro-4H-pyrazol-4-ylidene)(phenyl)methyl]benzohydrazide (HL1), which was characterized by NMR spectroscopy and single-crystal X-ray structure study. X-ray diffraction analyses of the crystals revealed a nonplanar molecule, existing in the keto-amine form, with intermolecular hydrogen bonding forming a seven-membered ring system. The reaction of HL1with Co(II), Ni(II), and Cu(II) halides gave the corresponding complexes, which were characterized by elemental analysis, molar conductance, magnetic measurements, and infrared and electronic spectral studies. The compounds were screened for theirin vitrocytotoxic activity against HL-60 human promyelocytic leukemia cells and antimicrobial activity against some bacteria and yeasts. Results showed that the compounds are potent against HL-60 cells with the IC50value ≤5 μM, while some of the compounds were active against few studied Gram-positive bacteria.


2018 ◽  
Vol 73 (8) ◽  
pp. 571-575
Author(s):  
Yang Jie ◽  
Huang Yuan ◽  
Zhong YouQuan ◽  
Fang Ting ◽  
Hao Fan ◽  
...  

AbstractA new complex [(CH3)3NH]2[Co(NCS)4], in which zero-dimensional [Co(NCS)4]n2− anions are balanced by 2n [(CH3)3NH]+ cations, was synthesized. The complex has been characterized by single X-ray diffraction, infrared spectroscopy, elemental analysis, and magnetic measurements. Magnetic susceptibility data indicate ferromagnetic interactions among the CoII ions.


2000 ◽  
Vol 634 ◽  
Author(s):  
P. Allia ◽  
M. Baricco ◽  
E. Bosco ◽  
M. Coisson ◽  
D. Falletti ◽  
...  

ABSTRACTRapidly solidified Au80Fe20 ribbons were prepared either by melt spinning or by solidstate quenching of a homogenised master alloy. The as-quenched sample displays a paramagnetic behavior indicating a perfect solid solution of Fe in the Au matrix. Subsequent anneals have been performed to induce the precipitation of Fe particles. X-ray diffraction technique have been exploited to determine the alloy microstructure. The structural stability have been studied by measuring electrical properties in isothermal and tempering condition. The variation of magnetisation and electrical resistance have been measured after submitting the samples to plastic deformation. A logarithmic relaxation of the electrical resistance is observed in all studied samples after deformation. Magnetic hysteresis loops have been measured in as-quenched and annealed samples at different temperatures. X-ray diffraction and magnetic measurements indicate that thermal treatments have been successful in inducing the precipitation of both bcc and fcc Fe clusters.


2017 ◽  
Vol 72 (3) ◽  
pp. 171-174
Author(s):  
Kun Qian ◽  
Yan-hong Yu ◽  
Yao-Hui Ye ◽  
Hao Fan

Abstract A new complex [C(NH2)3]2[Mn(N3)4], in which MnII cations are alternatively bridged by double EE azide-bridges and the [Mn(N3)4]n2− chains are separated by guanidinium cation bilayers, has been synthesized and characterized by single crystal X-ray diffraction, infrared (IR) spectroscopy, elemental analyses, and magnetic measurements. Magnetic susceptibility data indicate antiferromagnetic interaction among the MnII ions.


2003 ◽  
Vol 58 (10) ◽  
pp. 1009-1014 ◽  
Author(s):  
Subrata Kumar Dey ◽  
Bappaditya Bag ◽  
Dilip Kumar Dey ◽  
V. Gramlich ◽  
Yadong Li ◽  
...  

The synthesis, structure, and physical properties of a series of mononuclear complexes viz. [Cu(L)2] 1, [CuL2(CH3O)2] 2 and [Zn(L)2] 3 (where L = 1-Phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP)) are presented. The complexes were characterized by elemental analysis, IR and electronic spectroscopy (1 and 2), magnetic measurements at room temperature (1 and 2) and thermogravimetric analysis. The structures of all the three complexes were determined by single crystal X-ray diffraction studies. The coordination geometry around complexes CuL2 (1) and ZnL2 (3) is slightly distorted square planar while the geometry around Cu(II) of [Cu(L)2(CH3O)2] (2) is distorted octahedral with four oxygen atoms of two PMBP ligand occupying the equatorial positions and two methanol molecules occupying the two axial positions.


1985 ◽  
Vol 50 (6) ◽  
pp. 1383-1390
Author(s):  
Aref A. M. Aly ◽  
Ahmed A. Mohamed ◽  
Mahmoud A. Mousa ◽  
Mohamed El-Shabasy

The synthesis of the following mixed ligand complexes is reported: [Ni(phdtc)2(dpm)2], [Ni(phdtc)2(dpe)2], [Ni(phdtc)2(dpp)3], [Ni(1-naphdtc)2(dpm)2], [Ni(1-naphdtc)2], and [Ni(1-naphdtc)2(dpp)2], where phdtc = PhNHCSS-, 1-naphdtc = 1-NaPhNHCSS-, dpm = Ph2PCH2PPh2, dpe = Ph2P(CH2)2PPh2, and dpp = Ph2P(CH2)3PPh2. The complexes are characterised by microanalysis, IR and UV-Vis spectra, magnetic measurements, conductivity, X-ray powder diffraction, and thermal analysis. All the mixed ligand complexes are diamagnetic, and thus a square-planar or square-pyramidal (low-spin) structure was proposed for the present complexes.


2008 ◽  
Vol 73 (1) ◽  
pp. 24-31
Author(s):  
Dayu Wu ◽  
Genhua Wu ◽  
Wei Huang ◽  
Zhuqing Wang

The compound [Cd(4,4'-bpy)2(H2O)2](ClO4)2·(L)2 was obtained by the reaction of Cd(ClO4)2, bis(1-pyrazinylethylidene)hydrazine (L) and 4,4'-bipyridine in aqueous MeOH. Single-crystal X-ray diffraction has revealed its two-dimensional metal-organic framework. The 2-D layers superpose on each other, giving a channel structure. The square planar grids consist of two pairs of shared edges with Cd(II) ion and a 4,4'-bipyridine molecule each vertex and side, respectively. The square cavity has a dimension of 11.817 × 11.781 Å. Two guest molecules of bis(1-pyrazinylethylidene)hydrazine are clathrated in every hydrophobic host cavity, being further stabilized by π-π stacking and hydrogen bonding. The results suggest that the hydrazine molecules present in the network serve as structure-directing templates in the formation of crystal structures.


Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1885
Author(s):  
Xinyu Wu ◽  
Feng Yang ◽  
Jian Gan ◽  
Zhangqian Kong ◽  
Yan Wu

The silver particles were grown in situ on the surface of wood by the silver mirror method and modified with stearic acid to acquire a surface with superhydrophobic and antibacterial properties. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and X-ray energy spectroscopy (XPS) were used to analyze the reaction mechanism of the modification process. Scanning electron microscopy (SEM) and contact angle tests were used to characterize the wettability and surface morphology. A coating with a micro rough structure was successfully constructed by the modification of stearic acid, which imparted superhydrophobicity and antibacterial activity to poplar wood. The stability tests were performed to discuss the stability of its hydrophobic performance. The results showed that it has good mechanical properties, acid and alkali resistance, and UV stability. The durability tests demonstrated that the coating has the function of water resistance and fouling resistance and can maintain the stability of its hydrophobic properties under different temperatures of heat treatment.


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