• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.4
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• pp.294-297
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• 2013

ZnO crystals with octahedral shape were synthesized by thermal evaporation technique. $ZnF_2$ powder was used as the source material. The thermal evaporation and oxidation of $ZnF_2$ powder was carried out for 1 hr at $1,000^{\circ}C$ in air under atmospheric pressure. SEM images showed that the ZnO crystals produced by oxidizing $ZnF_2$ vapor possessed a characteristic octahedral shape. XRD spectrum revealed that the ZnO octahedron had hexagonal wurtzite structure. In the room temperature photoluminescence spectrum, a strong green emission peak at around 510 nm was observed.

• Korean Journal of Metals and Materials
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• v.49 no.12
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• pp.977-982
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• 2011

Migration and interaction of multi-protons in a zinc-doped barium zirconate (Zn-doped $BaZrO_3$) super cell were investigated using a density functional theory. O ions in the super cell form interconnected octahedrons with Zr or Zn ions positioned in their centers and Ba ions positioned among the eight octahedrons. When one proton was added to the super cell, the energy barrier of 0.80 eV for proton transfer from the first to second nearest O ion sites from the Zn ion reached its highest value. When two protons were added to the super cell, the two protons preferred the first nearest O ions from the Zn ion. The two protons were accommodated by pushing the neighboring Zn ion further away from the center of the octahedron. Energy barriers for proton transfer from the Zn-octahedron to the neighboring Zr-octahedron were spread in the range of 0.36 ~ 1.02 eV.

• Journal of the Korean Ceramic Society
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• v.30 no.6
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• pp.499-509
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• 1993

Structures of hematite(${\alpha}$-Fe2O3), Ba-ferrite(BaFe12O19) and Zn2Y(Ba2Zn2Fe12O22) were studied by powder X-ray diffraction(XRD) method. Powder XRD patterns of the ferrites were analyzed with the Rietveld method, and the final refined R-factors were RWP<0.01 and RI<0.03. The lattice parameters refined with hexagonal crystal system were a=5.0342${\AA}$, c=13.746${\AA}$ for hematite, a=5.8928${\AA}$, c=23.201${\AA}$ for Ba-ferrite, and a=5.8763${\AA}$, c=43.567${\AA}$ for Zn2Y. In the hematite, the oxygen parameter is 0.3072 and the Fe-O distances in FeO6octahedron are 1.941${\AA}$ and 2.118${\AA}$, close to the single crystal data of Blake et al.. In the Ba-ferrite, the Fe atom in oxygen trigonal bipyramid is displaced 0.155${\AA}$ away from the BaO3 mirror plane into 4e position. In the Zn2Y, 75% of Zn is located at the oxygen terahedral site in S-block.

• Korean Journal of Crystallography
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• v.13 no.1
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• pp.17-20
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• 2002

The complex [Zn(L)₂(H₂O)₄] (1) (L = isonicotinate) has been prepared and characterized by X-ray crystallography. Compound 1 crystallizes in the triclinic space group P1, with a = 6.9062(4) , b = 9.2618(7) , c = 6.3313(3) , α = 104.986(6)°, β = 112.865(4)°, γ = 96.213(6)°, V = 350.41(4) , Z = 1, R₁(wR₂) for 1225 observed reflections of [I > 2σ(I)] was 0.0209 (0.0591). The coordination environment of the zinc atom can be described as an octahedron in which the isonicotinato ligands are mutually trans. Compound 1 is also connected into a two-dimensional chain via hydrogen-bonds.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1697-1702
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• 2014

A novel complex [$Zn(phen)(o-AB)_2$] [phen: 1,10-phenanthroline o-AB: o-aminobenzoic acid] was synthesized and characterized by elemental analysis and X-ray diffraction single-crystal analysis. The crystal crystallizes in monoclinic, space group P2(1)/c with $a=7.6397(6){\AA}$, $b=16.8761(18){\AA}$, $c=17.7713(19){\AA}$, ${\alpha}=90^{\circ}$, ${\beta}=98.9570(10)^{\circ}$, ${\gamma}=90^{\circ}$, $V=2.2633(4)nm^3$, Z = 4, F(000) = 1064, S = 1.058, $Dc=1.520g{\cdot}cm^{-3}$, $R_1=0.0412$, $wR_2=0.0948$, ${\mu}=1.128mm^{-1}$. The Zn(II) is six coordinated by two nitrogen and four oxygen atoms from the 1,10-phenanthroline and o-aminobenzoic acid to furnish a distorted octahedron geometry. The complex exhibits intense fluorescence at room temperature. Theoretical studies of the title complex were carried out by density functional theory (DFT) B3LYP method. CCDC: 898291.

• Bulletin of the Korean Chemical Society
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• v.18 no.6
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• pp.653-656
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• 1997

The new unsymmetric $N_6$ ligand 1-amino-13-(2-pyridyl)-3,6,9,12-tetraazatridecane (aptatd) containing one pyridyl group has been synthesized and characterized by EA, IR, and NMR. Its proton association constants $(log K_H^n)$ and stability constants $(log K_{ML})$ for Co(Ⅱ), Ni(Ⅱ), Cu(Ⅱ), and Zn(Ⅱ) ions were determined at 298.1 K and ionic strength 0.100 mol $dm^{-3}$ (KNO₃) in aqueous solution by potentiometry: log $K_H^1$=8.80, log $K_H^2$=8.49, log $K_H^3$=6.84, log $K_H^4$=4.17, log $K_H^5$=3.47; log $K_{ML}(Co^{2+})$=18.00, log $K_{ML}(Ni^{2+})$=21.31, log $K_{ML}(Cu^{2+})$=23.62, log $K_{ML}(Zn^{2+})$=15.60. The X-ray structure of its nickel(Ⅱ) complex [Ni(aptatd)]$(ClO_4)_2$ are reported: orthorhombic space group Pbca, a=15.715(1) Å, b=14.280(2) Å, c=19.443(2) Å, V=4363.4 (9) ų with Z=8. The geometry around nickel is a distorted octahedron with the pyridine nitrogen atom being cis to the nitrogen atom of the terminal primary amine.