• Journal of the Korean Chemical Society
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• v.44 no.2
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• pp.166-169
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• 2000

• Journal of the Korean Chemical Society
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• v.42 no.4
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• pp.13-482
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• 1998

• Journal of the Korean Chemical Society
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• v.26 no.2
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• pp.81-87
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• 1982

The monooxo-bridged binuclear molybdenum(V) complexes, $Mo_2O_3(NCS)_4(Bipy)_2\;(Bipy = bipyridine),\;Mo_2O_3(NCS)-4(Phen)-2$ (Phen = 1,10-phenanthroline), and $Mo_2O_3(NCS)_4(Ox)_2(OxH)_2$ (Ox = oxinato and OxH = oxine) have been prepared. Their electronic and IR spectra, electric conductivity, and magnetic susceptibility were measured. From the results all of th complexes turned out to be electroneutral dimers with about 0.5 BM, and in the oxine complex, $Mo_2O_3(NCS)_2(Ox)_2(OxH)_2$, the oxine seems to bind partly as monodentate and partly as bidentate molecule.

• Bulletin of the Korean Chemical Society
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• v.25 no.1
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• pp.37-41
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• 2004

A new tridentate ligand incorporating a monoxime and thiosemi-carbozone moieties has been synthesized. Its copper(II), nickel(II) and palladium(II) complexes have been prepared and characteirzed by physical and spectral methods. Elemental analyses and spectroscopic data of the metal complexes are consistent with the formation of a mononuclear copper(II) complex and binuclear complex with both nickel(II) and palladium(II). In the copper(II) complex the fourth coordination site is occupied by nitrate ion. In the binculear complexes the fourth coordination site is occupied by the deprotonated oxime oxygen of the ligand coordinated to the other metal.

• Bulletin of the Korean Chemical Society
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• v.26 no.4
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• pp.634-640
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• 2005

The reaction of cis-[Cr([14]-decane)(OH$_2)_2]^+$ ([14]-decane = rac-5,5,7,12,12,14-hexamethyl-1,4,8,11-teraazacyclotetradecane) with auxiliary ligands {$L_a$ = citrate(cit)} leads to a new dimeric complex cis-[{Cr([14]-decane)($\mu$-cit)}$_2](ClO_4)_2$. This binuclear complex has been structurally characterized by a combination of elemental analysis, conductivity, IR and Vis spectroscopy, mass spectrometry, and X-ray crystallography. Analysis of the crystal structure of cis-[{Cr([14]-decane)($\mu$-cit)})($_2]^+$ reveals that each chromium has a distorted octahedral coordination environment and citrato ligands are monodentate to the two chromium atoms via the carboxyl groups. For dimeric complex the bridging geometry is as follows: Cr$\ldots$Cr = 7.361 $\AA$; Cr-O(average) = 1.958 (8) $\AA$; Cr-N range = 2.108 (9)-2.147(9) $\AA$; N(1)-Cr-N(3) (equatorial position) = 98.0(4)$^{\circ}$; N(2)-Cr-N(4) (axial position) = 166.4(4)$^{\circ}$; O(1)-Cr-N(2) = 98.1(4)$^{\circ}$; O(3)-Cr-N(4) = 96.6(3)$^{\circ}$; O(1)-Cr-O(3) = 90.4$^{\circ}$. The FAB mass spectrum of the dimeric complex displays peak due to the molecular ions cis-[{Cr([14]-decane)($\mu$-cit)})($_2]^+$ at m/z 1053.

• Bulletin of the Korean Chemical Society
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• v.11 no.4
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• pp.303-306
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• 1990

Kinetic studies were carried out for the redox reaction of $[Co(NH_3)_4(C_2O_4)]^+$ with aqueous $[Fe(H_2O)_6]^{2+}$ solution in the present of $H^+$ by UV/VIS-spectrophotometric method. It was found that the order of $H^+$ for the reaction is first one in the higher $H^+$ concentration range of $1.67×10^{-1} M{\sim}1.00 M,$ while second order in the lower range of $6.30×10^{-2} M{\sim}1.67{\times}10^{-1} M.$ Reaction order of the substrates was found to be first order with respect to each of them. Accordingly overall reactions are third or fourth order. The results of calculation for the Extended Huckel Molecular Orbital theory contribute to estimate the preferred intermediates, bridging form of binuclear complex. On the basis of these results, we propose that this redox reaction proceed via inner-sphere reaction mechanism.

• Journal of the Korean Chemical Society
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• v.36 no.2
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• pp.223-229
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• 1992

Mechanistic studies on the metal-exchange reactions of sparteine copper(II) dichloride [$SpCuCl_2$] with Hg(II) ion and Hg(0) metal have been carried out with the aid of Cyclic Voltammetry and UV-visible spectrophotometry. The metal exchange reaction of $SpCuCl_2$ with both Hg(II) ion and Hg(0) metal follows pseudo-first order kinetics. Rate constants and activation parameters of metal exchange reaction have been evaluated and reported. Experimental results indicate that the rate determining step for the exchange reaction is the cleavage of Cu(II)-N bond in the transient binuclear complex of Cu(II) and mercury(II) bound to sparteine ligand.

• Bulletin of the Korean Chemical Society
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• v.29 no.9
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• pp.1711-1716
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• 2008

The reaction of copper(II) chloride with phenyl-N-[(pyridine-2-yl)methylene]methaneamide (ppmma) leads to a new $\mu$ -chloro bridged dimeric [Cu(ppmma)$Cl_2$]$_2$ complex, whereas a reaction of copper(II) bromide with ppmma affords a monomeric Cu(ppmma)$Br_2$ complex. Both complexes have been characterized by X-ray crystallography and electronic absorption spectroscopy. The crystal structural analysis of [Cu(ppmma)$Cl_2$]$_2$ shows that the two Cu(II) atoms are bridged by two chloride ligands, forming a dimeric copper(II) complex and the copper ion has a distorted square-pyramidal geometry ($\tau$ = 0.2). The dimer units are held through a strong intermolecular $\pi-\pi$ interactions between the nearest benzyl rings. On the other hand, Cu(ppmma)Br2 displayed a distorted square planar geometry with two types of strong intermolecular π-π interaction. EPR spectrum of [Cu(ppmma)$Cl_2$]$_2$ in frozen glas s at 77 K revealed an equilibrium between the mononuclear and binuclear species. The magnetic susceptibilities data of [Cu(ppmma)$Cl_2$]$_2$ and Cu(ppmma)$Br_2$ follow the Curie-Weiss law. No significant intermolecular magnetic interactions were examined in both complexes, and magnetic exchange interactions are discussed on the basis of the structural features.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1021-1025
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• 2009

A novel supramolecular network containing binuclear copper unit $[Cu(phen)_{2}({\mu}-ID\;A)Cu(phen){\cdot}(NO_{3})](NO_{3}){\cdot}4(H_{2}O)$ (1) was synthesized through the self-assembly of iminodiacetic acid ($H_2IDA$) and 1,10-phenanthroline (phen) in the condition of pH = 6. It has been characterized by the infrared (IR) spectroscopy, elemental analysis, single crystal X-ray diffraction, and thermogravimetric analysis (TGA). 1 shows a 2-D supramolecular structure assembled through strong and unique $\pi-\pi$ packing interactions. Density functional theory (DFT) calculations show that theoretical optimized structures can well reproduce the experimental structure. The TGA and powder X-ray diffraction (PXRD) curves indicate that the complex 1 can maintain the structural integrity even at the loss of free water molecules. The magnetic property is also reported in this paper.

• Bulletin of the Korean Chemical Society
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• v.21 no.6
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• pp.571-576
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• 2000

Electrocatalytic effects for the reduction of thionyl chloride in $LiAICI_4/SOCl_2$ electrolyte solution containing Schiff base M(II) (M; Co and Fe) complexes are evaluated by determining kinetic parameters with cyclic voltammetry and chronoamperometry at a glassy carbon electrode. The charge transfer process during the reduction of thionyl chloride is affected by the concentration of the catalyst. The catalytic effects are demonstrated from both a shift of the reduction potential for the thionyl chloride toward a more positive direction and an increase in peak currents. Catalytic effects are larger in thionyl chloride solutions containing the binuclear [M(II) $_2$ (TSBP)] complex rather than mononuclear [M(II)(BSDT)] complexes. Significant improvements in the cell performance have been noted in terms of both thermodynamics and activation energy for the thionyl chloride reduction. The activation energy calculated from the Arrhenius plots is 4.5-5.9 kcal/mole at bare glassy carbon electrodes. The activation energy calculated for the catalyst containing solution is 3.3-4.9 kcalmole, depending on whether the temperature is lowered or rasied.