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
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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
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Tetranuclear Cu(II) complex with [2+4] Cu4O4 cubane based core framework derived from 2-[{2-(1-hydroxy-ethyl)-phenylimino}-methyl]-6-methoxy-phenol: Quantifying conventional and unconventional interactions and QTAIM analysis
TL;DR: A cubane based tetranuclear copper(II) complex prepared using 2-[{2-(1-hydroxy-ethyl)-phenylimino}-methyl]-6-methoxy-phenol and copper (II) acetate has been characterized by spectral techniques and single-crystal X-ray diffraction studies as discussed by the authors .
Journal ArticleDOI
Chiral tetranuclear copper(II) complexes: synthesis, optical and magnetic properties
Naushad Ahmed,Shalini Tripathi,Arup Sarkar,Kamal Uddin Ansari,Chinmoy Das,Neetu Prajesh,Satoshi Horike,Satoshi Horike,Ramamoorthy Boomishankar,Maheswaran Shanmugam +9 more
TL;DR: In this paper, the chiral tetranuclear cubane complexes with the general molecular formula [Cu4(R-L1)4] (R-1) and [C4(S-L 1) 4] (S-1), which are characterized by single-crystal X-ray diffraction were characterized.
Journal ArticleDOI
Catena-poly[[[2,4-dichloro-6-{[(2-hydroxyethyl)imino]methyl}phenolato-n-3,o,o']-copper(ıı)]--chlorido]monohydrate]: synthesis, structural, spectroscopic and luminescent properties
TL;DR: A new chloride bridged polymeric Cu(II) complex, [Cu(HL)(μ-Cl).H2O]n, 1, (H2L = 2,4-dichloro-6-{[(2-hydroxyethyl)imino]methyl}phenol) has been synthesized and characterized by elemental-spectral an...
Journal ArticleDOI
Synthesis, crystal structure, and magnetic property of a stepped tetranuclear copper(II) complex of 3,5-diisopropylpyrazole-1-methoxide
TL;DR: In this article, the tetranuclear copper(II) complex (dippmO)CuCl]4 (1) was shown to have strong antiferromagnetic interactions through the oxo groups within the dimeric units (J1 ǫ = 0.239 cm−1) and weak antiferromeagnetic couplings between the dimers (J2 Ã = −15 cm− 1).
Journal ArticleDOI
Tetranuclear nickel cubane cluster formed by the hydrolysis of nickel koneramine complex
Sakthi Raje,Raja Angamuthu +1 more
TL;DR: In this article, the structural, electrochemical, thermal and physical properties of the Ni4(μ3-O)4 cubane cluster were studied and reported in terms of structural and electrochemical properties.
References
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A short history of SHELX
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Synthesis, structure, and spectroscopic properties of copper(II) compounds containing nitrogen–sulphur donor ligands; the crystal and molecular structure of aqua[1,7-bis(N-methylbenzimidazol-2′-yl)-2,6-dithiaheptane]copper(II) perchlorate
TL;DR: In this article, the linear quadridentate N2S2 donor ligand 1,7-bis(N-methylbenzimidazol-2′-yl)-2,6-dithiaheptane (bmdhp) forms mono-and di-hydrate 1 : 1 copper(II) complexes which are significantly more stable toward autoreduction than those of the non-methylated analogue.