• Bulletin of the Korean Chemical Society
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• 제19권2호
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• pp.231-235
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• 1998

Two holmium β-diketonate complexes, Ho(hfa)3(H2O)2 (1) and [Ho(hfa)3(H2O)2](triglyme) (2), have been prepared and characterized by IR, TGA, and single-crystal X-ray analyses. These complexes show polymeric chains by the intermolecular hydrogen bondings. The donor atoms of the intermolecular hydrogen bonding in both complexes are hydrogen atoms of the coordinated water molecules. The acceptor atoms in 1 are the carbonyl oxygen atoms of β-diketonate ligands whereas those in 2 are oxygen atoms of the triglyme ligand. While compound 1 decomposes cleanly to Ho2O3, compound 2 sublimes intact. Crystal data for 1 and 2 are as follows: Ho(hfa)3(H2O)2 triclinic P1, a=10.158(4), b=11.628(2), c=12.579(6) Å, α=67.02(3)°, β=73.95(4)°, γ=76.12(2)°, V=1299.8(8) Å3. [Ho(hfa)3(H2O)2](triglyme), monoclinic P21/c, a=12.559(3), b=19.111(2), c=16.789(6) Å, β=110.59(4)°, V=3772(2) Å3.

• 분석과학
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• 제28권3호
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• pp.204-211
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• 2015

란탄족 착물은 독특한 발광 특성으로 인하여 많은 연구가 되고 있는 물질이다. 유로피움(III) β-디케토네이트 착물에 아민계열 또는 포스핀옥사이드계열 리간드를 추가로 배위 결합시켜 발광 효율을 비교하였으며, 아민계열 배위보다는 발광 효율 증진에는 포스핀옥사이드 계열이 더 좋은 추가 리간드임을 확인하였다. 그 중에서도 트리옥틸포스핀 옥사이드를 배위시켰을 때 가장 높은 발광효율이 관찰되었다. 추가로 배위될 수 있는 트리옥틸포스핀 옥사이드의 당량을 확인하기 위해서 ³¹P-NMR과 photoluminescence를 분석하였다. 유로피움(III) β-디케토네이트 화합물은 리간드의 입체장애에 따라 트리옥틸포스핀 옥사이드의 배위 당량은 1 개 또는 2 개가 가능함을 확인하였다.

• Bulletin of the Korean Chemical Society
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• 제23권6호
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• pp.921-923
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• 2002

• Bulletin of the Korean Chemical Society
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• 제19권4호
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• pp.484-486
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• 1998

• Bulletin of the Korean Chemical Society
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• 제20권11호
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• pp.1257-1260
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• 1999

• Bulletin of the Korean Chemical Society
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• 제17권11호
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• pp.1023-1031
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• 1996

A new synthetic route for the lanthanum β-diketonate compounds via in-situ formed lanthanum alkyl complexes was developed in the process for the development of suitable MOCVD (metal-organic chemical vapor deposition) precursors of PLT, one of the promising material for the ferroelectric film. A series of lanthanum β-diketonate compounds were successfully synthesized by this method. This new method is found to have some merits; versatile method for almost every β-diketone, β-hydroxyketone, and β-hydroxyaldehyde, short reaction time, easy purification for high purity, moderate to high yield, and easy access to anhydrous compounds. In some cases, anhydrous oligomeric products fail to show the higher volatility. On the other hand, some lanthanum β-diketonates with aromatic groups such as La(1,3-biphenyl-l,3-propandione)3 are found to have favorable properties for a precursor of lanthanum oxide, one of major components of PLT, such as low melting point, and much higher decomposition temperature. A plausible pyrolysis mechanism is proposed by the TGA, where consecutive dissociation of R, CO, CH, C, and O fragments occurs.

• Bulletin of the Korean Chemical Society
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• 제17권7호
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• pp.637-642
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• 1996

Preparation and properties of potential CVD (Chemical Vapor Deposition) precursors for the TiO2, a major component of the perovskite materials such as PT, PLT, PZT, and PLZT were investigated. Reactions between β-diketones and TiMe3, formed in situ failed to produce stable Ti(β-diketonate)3 complexes but a stable purple solid, characterized as (OTi(BPP)2)2 (BPP=1,3-biphenyl-1,3-propanedione) was obtained when BPP was used. Several new Ti(Oi-Pr)2(β-diketonate)2 complexes with aromatic or ring substituents were synthesized by the substitution reaction of Ti(OiPr)4by β-diketones and characterized with 1H NMR, IR, ICP, and TGA. Solid complexes such as Ti(Oi-Pr)2(BAC)2 (BAC=1.-phenyl-2,4-pentanedione), Ti(Oi-Pr)2(BPP)2, Ti(Oi-Pr)2(1-HAN)2 (1-HAN=2-hydroxy-1-acetonaphthone), Ti(Oi-Pr)2(2-HAN)2 (2-HAN=1-hydroxy-2-acetonaphthone), Ti(Oi-Pr)2(ACCP)2 (ACCP=2-acetylcyclopentanone), and Ti(Oi-Pr)2(HBP)2 (HBP=2-hydroxybenzophenone) were found to be stable toward moisture and air. Ti(Oi-Pr)2(ACCP)2 and Ti(Oi-Pr)2(HBP)2 were proved to have lower melting points and higher decomposition temperatures. However, these complexes are thermally stable and pyrolysis under an inert atmosphere resulted in incomplete decomposition. Ti(Oi-Pr)2(DPM)2 (DPM=dipivaloylmethane) and Ti(Oi-Pr)2(HFAA)2 (HFAA=hexafluoroacetylacetone) were sublimed substantially during the thermal decomposition. Pyrolysis mechanism of these complexes are dependent on type of β-diketone but removal of Oi-Pr ligands occurs before the decomposition of β-diketonate ligands.

• 대한화학회지
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• 제37권9호
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• pp.806-812
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• 1993

Cu(I)(${\beta}$-diketonate) 착화합물로서 $Cu(I)(hfac)PR_3$(P는 phosphine, R은 Me, Et, Bu를 나타낸다) 착물들을 비수용매에서 유리질 탄소전극과 탄소 microelectrode를 사용하여 이들 착물들의 전기화학적 성질을 조사하였다. 아세토니트릴 용액에서 순환 전압-전류법에 의한 $Cu(I)(hfac)PR_3$ 착물들의 환원과정은 최종생성물이 Cu(0)로 가는 1전자 반응으로 진행되었다. 탄소 microelectrode를 이용한 대시간-전류법에 의해서 이들 착물들이 1전자 반응으로 진행됨을 확인하였으며, 확산계수는 $4.5{\sim}6.7{\times} 10^{-6}cm^2$/sec값으로 나타났다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.364.2-364.2
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• 2014

Magnesium oxide (MgO) thin films have attracted great scientific and technological interest in recent decades. Because of its distinguished properties such as a wide band gap (7.2 eV), a low dielectric constant (9.8), a low refractive index, an excellent chemical, and thermal stability (melting point=$2900^{\circ}C$), it is widely used as inorganic material in diverse areas such as fire resistant construction materials, optical materials, protective layers in plasma display panels, buffer layers of multilayer electronic/photonic devices, and perovskite ferroelectric thin films. Precursor used in the ALD requires volatility, stability, and low deposition temperature. Precursors using a heteroleptic ligands with different reactivity have advantage of selective reaction of the heteroleptic ligands on substrate during ALD process. In this study, we have synethesized new heteroleptic magnesium precursors ${\beta}$-diketonate and aminoalkoxide which have been widely used for the development of precursor because of the excellent volatility, chelating effects by increasing the coordination number of the metal, and advantages to synthesize a single precursor. A newly-synthesized Mg(II) precursor was adopted for growing MgO thin films using ALD.

• Bulletin of the Korean Chemical Society
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• 제20권3호
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• pp.355-361
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• 1999

To improve the volatility and stability of lead complexes, the principle of stabilization by saturating the metal coordination sphere by intramolecular coordination through a β-diketonates with an ethereal group has was tested. Several new lead complexes with alkoxyalkyl-substituted β-diketonates, Pb(R1C(O)CHC(O)(CH2)3OR2)2(Rl=t-Bu, Me, OMe, i-Pr, R2=Me, Et), or carboxylate, Pb(OC(O)(CH2)3OEt)2, were prepared by the reaction between Pb(OAc)2 and corresponding alkoxyalkyl-substituted β-diketonates, and they were found to have a viscous liquid phase. The nature of the head (β-diketonate or carboxylate) or tails and substituents of β-diketonates appeared not to be important for the formation of the liquid phase. It is worth mentioning that Pb(OAc)2, which has limited use due to its low solubility, was successfully adopted as a starting material for the preparation of new lead complexes. Easy hydrolysis, reaction with HCl, and 13C NMR spectra indicated that tail portions were not coordinated to the metal as a copper derivative, Cu(t-BuC(O)CHC(O)(CH2)3OMe)2. All these complexes were not volatile enough for the MOCVD experiments, but a methyl derivative, Pb(MeC(O)CHC(O)(CH2)3OEt)2, showed some sublimation. The methoxy derivative, Pb(MeOC(O)CHC(O)(CH2)3OEt)2, was thermally unstable due to possible equilibrium between species coordinating with a keto oxygen atom and an ethereal atom of a methoxy group, which was confirmed by IR and 13C NMR spectra.