• Title/Summary/Keyword: Coordination chemistry

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Copper(II) Coordination Polymers Assembled from 2-[(Pyridin-3-ylmethyl)amino]ethanol: Structure and Magnetism

  • Han, Jeong-Hyeong;Shin, Jong-Won;Min, Kil-Sik
    • Bulletin of the Korean Chemical Society
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    • v.30 no.5
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    • pp.1113-1117
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    • 2009
  • The one-dimensional coordination polymers, $[Cu^{II}(L)(NO_3)_2]_n$ (1) and {$[Cu^{II}(L)(NO_3)]{\cdot}2H_2O}_{2n} (2), were synthesized from $Cu(NO_3)_2{\cdot}3H_2O$ and 2-[(pyridin-3-ylmethyl)amino]ethanol (L, PMAE) in methanol by controlling the molar ratio of copper(II) salt. Copper(II) ion in 1 has one pyridine group of PMAE whose an aminoethanol group coordinates adjacent copper(II) ion. As the pyridine group is bonded to neighboring copper(II) ion, 1 becomes a one-dimensional chain. Contrary to 1, the structure of 2 shows that the oxygen atom of ethoxide group is bridged between two copper(II) ions, which forms a dinuclear complex. Additionally, the pyridine group of PMAE included one dinuclear unit is coordinated to the other dimeric one each other, which leads to a one-dimensional polymer. Due to the structural differences, 1 exhibits weak antiferromagnetic interaction, while 2 shows strong antiferromagnetic interaction. Due to direct spin exchange via oxygen of PMAE 2 has a much strong spin coupling than 1.

Calculation of the Dipole Moments for the Coordination Compounds with Organic Ligands such as $(C_2H_5)_2SO,\;(C_6H_5)_2SO,\;(C_6H_5)_2SeO,\;(C_6H_5)_3AsO,\;(C_6H_5)_3PBCl_3,\;and\;(C_2H_5)_2OZrCl_4$

  • Ahn, Sang-Woon;Kim, Hyung-Doo;Park, Eui-Suh
    • Bulletin of the Korean Chemical Society
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    • v.7 no.2
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    • pp.129-136
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    • 1986
  • The dipole moments for some coordination compounds with organic ligands have been calculated adopting the molecuar orbitals obtained from EHT calculation with modified technique. Adopting the molecular orbitals with the modified technique, the calculated dipole moments for all the coordination compounds with organic ligands give closer agreements with experimental values than those using the molecular orbitals obtained from EHT calculation. The calculated dipole moments suggest that $(C_2H_5)_2SO,\;(C_6H_5)_2SO,\;and\;(C_6H_5)_2SeO$ may have a trigonal planar structure and $(C_6H_5)_3AsO,\;and\;(C_6H_5)_3PBCl_3$ a square planar structure and $(C_2H_5)_2OZrCl_4$ may be distorted markedly. This work may also indicate that the modified technique is superior to the EHT calculation as far as the dipole moment calculation is concerned.

2D Coordination Polymer Derived Co3O4 Nanocrystals as High Performance Anode Material of Lithium-Ion Batteries

  • Wen, Hao;Shi, Changdong;Gao, Yuanrui;Rong, Hongren;Sha, Yanyong;Liu, Hongjiang;Liu, Qi
    • Nano
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    • v.13 no.12
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    • pp.1850139.1-1850139.10
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    • 2018
  • $Co_3O_4$ nanocrystals have been synthesized via an ordinary one-step calcination of a cobalt-based 2D coordination polymer [Co(tfbdc)(4,4'-bpy)$(H_2O)_2$]. As an anode material for lithium-ion batteries, the obtained $Co_3O_4$ nanocrystals exhibit high reversible capacity, excellent cyclic stability and better rate capability. The reversible capacity of the $Co_3O_4$ nanocrystals maintains $713mA\;h\;g^{-1}$ after 50 cycles at a current density of $50mA\;g^{-1}$. Our results confirm that searching for metal oxides nanomaterials used as anode materials of lithium ion batteries via the calcinations of 2D coordination polymer is a new route.

Endo- and Exo-Coordinated Mercury(II) Complexes of O3S2 Macrocycles: Effect of Dibenzo-Substituents on Coordination Mode

  • Lee, Ji-Eun;Kim, Hyun-Jee;Lee, So-Young;Lee, Jai-Young;Jin, Yong-Nu;Lee, Shim-Sung
    • Bulletin of the Korean Chemical Society
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    • v.28 no.11
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    • pp.2041-2044
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    • 2007
  • The reactions of mercury(II) chloride with O3S2-donor macrocyclic ligands with (L1) and without (L2) dibenzosubunit afforded respective exo- (1) and endo-coordinated (2) complexes depending on the ring rigidity of the ligands. From the X-ray crystal structures and comparative NMR studies for the complexes 1 and 2, it is confirmed that the resulting species with different coordination modes exist not only in solid state but also in solution state.

Folding of Coordination Polymers into Double-Stranded Helical Organization

  • Kim, Ho-Joong;Lee, Eun-Ji;Lee, Myong-Soo
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.248-248
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    • 2006
  • The notable feature of the Cu(II) coordination polymer investigated here is its ability to self-assemble into a double-stranded helical structure with regular grooves along the helical axis, through the combination of metal-chloride dimeric interactions and repulsive interactions, as an organizing force. It is also remarkable that the double-stranded helices self-organize into a 2-D columnar structure in both the bulk state and aqueous solution. These results represent a unique example that weak metal-ligand bridging interactions can provide a useful strategy to construct stable double-stranded helical nanotubes.

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Synthesis and Characterization of New Tetraaza Macrocycles Bearing Two or Four N-Methoxyethyl Pendant Arms and Their Copper(II) and/or Nickel(II) Complexes

  • Kang, Shin-Geol;Kim, Hyun-Ja;Kwak, Chee-Hun
    • Bulletin of the Korean Chemical Society
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    • v.31 no.9
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    • pp.2701-2704
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    • 2010
  • This work shows that both L2 and L3 bearing two and four N-$(CH_2)_2OCH_3$ groups, respectively, can be prepared selectively by the reaction of $L^1$ with 1-bromo-2-methoxyethane. The di-N-substituted macrocycle $L^2$ readily forms its copper(II) and nickel(II) complexes. The N-$(CH_2)_2OCH_3$ groups in $[CuL^2]^{2+}$ are coordinated to the metal ion, whereas those in $[NiL^2]^{2+}$ are not involved in coordination. Interestingly, $L^3$ reacts with $Cu^{2+}$ ion to form $[Cu(HL^3)]^{3+}$, in which one tertiary amino group is not involved in coordination.