Journal ArticleDOI
Two Tetranuclear Copper(II) Complexes with Open Cubane-Like Cu4O4 Core Framework and Ferromagnetic Exchange Interactions between Copper(II) Ions: Structure, Magnetic Properties, and Density Functional Study
Reads0
Chats0
TLDR
In this paper, two tetranuclear alkoxo-bridged copper(II) tridentate Schiff base complexes have been synthesized and structurally and magnetically characterized.Abstract:
Two alkoxo-bridged copper(II) tridentate Schiff base complexes [{Cu(H2L1)}4] (1) [H2L1 = N-(2-hydroxyethyl)-3,5-di-tert-butylsalicylaldimine] and {Cu(H2L2)}4 (2) [H2L2 = N-(2-hydroxyethyl)-4-methoxysalicylaldimine] have been synthesized and structurally and magnetically characterized. X-ray diffraction studies show that 1 and 2 are tetranuclear alkoxo-bridged copper(II) complexes that contain a rather distorted Cu4O4 cubane core of 4+2 type (four short and two long Cu···Cu distances). The coordination of each copper ion can be described as a distorted square pyramid with one nitrogen and four oxygen atoms from three ligands. Variable-temperature magnetic susceptibility measurements on the two tetranuclear complexes 1 and 2 in the range 2–300 K indicate ferromagnetic exchange coupling between copper(II) centers. The magnetic susceptibility data were analyzed by using a simple two-J model with J′ and J″ representing the magnetic exchange couplings through the short and long Cu···Cu exchange pathways, respectively. The J values were as follows: J′ = +28.7 cm–1 and J″ = +7.8 cm–1 for 1, and J′ = +39.8 cm–1 and J″ = +10.2 cm–1 for 2. The sign and magnitude of the exchange coupling constants were justified on the basis of the structural geometric factors of the bridging Cu(O)2Cu fragments, the overlap of the magnetic orbitals, and DFT calculations.read more
Citations
More filters
Journal ArticleDOI
Cubane-like tetranuclear Cu(II) complexes bearing a Cu4O4 core: crystal structure, magnetic properties, DFT calculations and phenoxazinone synthase like activity
Shipra Sagar,Swaraj Sengupta,Swaraj Sengupta,Antonio J. Mota,Shyamal Kumar Chattopadhyay,Arturo Espinosa Ferao,Eric Rivière,William Lewis,Subhendu Naskar +8 more
TL;DR: Two new copper complexes 3a and 3b with a Cu4O4 cubane core are reported, and the first analysis of single crystal X-ray diffraction studies reveals that both molecules possess a [4 + 2] cubane-type core, and low temperature magnetic measurements show antiferromagnetic behaviour, in agreement with DFT calculations.
Journal ArticleDOI
Catecholase and phenoxazinone synthase activities of a ferromagnetically coupled tetranuclear Cu(II) complex
Merry Mitra,Tanay Kundu,Gurpreet Kaur,Gyaneswar Sharma,Angshuman Roy Choudhury,Yogesh Singh,Rajarshi Ghosh +6 more
TL;DR: A tetranuclear Cu(II) complex [CuII4(L)4] (1) [H2L = N-(2-hydroxyethyl)-3-methoxysalicylaldimine] is found to show overall ferromagnetic exchange coupling as mentioned in this paper.
Journal ArticleDOI
Experimental and quantum computational study of two new bridged copper(II) coordination complexes as possible models for antioxidant superoxide dismutase: Molecular structures, X-band electron paramagnetic spectra and cryogenic magnetic properties
Yogendra Singh,Ram N. Patel,Satish Kumar Patel,Abhay K. Patel,Neetu Patel,R Singh,Ray J. Butcher,Jerry P. Jasinski,Angel Gutiérrez +8 more
TL;DR: In this article, two bridged copper(II) coordination complexes with NNO donor ligands were characterized using a dual approach comprising experimental and quantum computational studies, and the magnetic exchange coupling constant (J) between the Cu(1)⋯Cu(2) centers for 1 and 2 were determined to be J
Journal ArticleDOI
Hydroxo-bridged copper(II) cubane complexes
TL;DR: Oxygen-bridged tetranuclear copper complexes having a Cu4O4 cubane-like core represent a really fascinating class of compounds, due to their similarity to copper oxidase active sites or to their molecular magnetism as mentioned in this paper.
Journal ArticleDOI
New mixed valence defect dicubane cobalt(II)/cobalt(III) complex: Synthesis, crystal structure, photoluminescence and magnetic properties
Mustafa Burak Coban,Elif Gungor,Hulya Kara,Hulya Kara,Ulrich Baisch,Ulrich Baisch,Yasemin Acar +6 more
TL;DR: In this article, a defect dicubane cobalt(II)/cobalt(III) was synthesized and characterized by element analysis, FT-IR, solid UV-Vis spectroscopy and single crystal X-ray diffraction.
References
More filters
Journal ArticleDOI
A pseudo cubic tetranuclear copper cluster: Synthesis, structure and magnetic property
TL;DR: In this paper, a pseudo-cubic Cu 4 O 4 skeleton was constructed by using Schiff base ligand and characterized by X-ray single crystal diffraction, FT-IR, elemental analysis and TG analysis.
Journal ArticleDOI
Structure, magnetic and ion-exchange properties of self-assembled triaza-copper(II)-oxalate hybrides having nanoscale one-dimensional channel.
TL;DR: The inter-replacement of perchlorate and hexafluorophosphate anions in solid 1 proves its porous structure, and the single crystal X-ray analysis provides 1 as a three-dimensional network, which contains two-dimensional permanent ring forming nanoscale one-dimensional channels.
Journal ArticleDOI
Relation between Magnetic, Spectroscopic and Structural Properties of Binuclear Copper(II) Complexes of Pentadentate Schiff-base Ligand, Semi-empirical and ab-initio Calculations
TL;DR: In this article, the structure of the Cu2(L 1 )(3,5 prz) complex was determined by x-ray diffraction, revealing their antiferromagnetic coupling.
Journal ArticleDOI
Cycloaddition of salicylaldehyde to nitrile: Synthesis and characterization of new macrocyclic copper(II) complexes bearing a heterobicyclic functional pendant arm
TL;DR: In this paper, Salicylaldehyde reacts with one of the N -CH 2 CN pendant arms of [CuL 1 ] 2+ (L 1 ǫ = 2,13-bis( N -cyanoethyl)-3,14-dimethyl-2,6,13,17-tetraazatricyclo[16.4.0 7.12 ]docosane) to produce [CuC 2 ] 2+, bearing one 1-hydroxy-2-aza-4-oxanaphthalene ring.
Journal ArticleDOI
Oxidative DNA cleavage promoted by polynuclear copper complexes bearing iminodiacetate chelator
TL;DR: It is suggested that the replacement of BPA chelator with the anionic IDA chelator alters distinctly the DNA cleavage behavior of rigid-spaced polycopper complexes.