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dc.description.abstractThe work presented in Part I is a compilation of synthesis and characterizations of new Zintl compounds. We have been interested in air-stable Zintl phases with complex anionic frameworks composed of heavier elements designed to be narrow band-gap semiconductors and then could be applied to thermoelectric materials. To achieve this, alkaline earths and divalent rare-earth elements were chosen in conjunction with transition metals, group 13 elements, and electronegative group 15 elements. This approach led to several air-stable anisotropic main group Zintl phases, Eu_(5)In_(2)Sb_(6), Ba_(3)Ga_(4)Sb_(5), and Eu_(7)Ga_(6)Sb_(8). These compounds are prepared by direct melting method of the reactants. Also several anisotropic transition metal Zintl phases, Yb_(9)Zn_(4)Sb_(9), Eu_(10)Mn_(6)Sb_(13), Sr_(2)MnSb_(2), and Sr_(11)Cd_(6)Sb_(l2), were synthesized by high-temperature Sn flux methods. Measurements of the electrical conductivity, Seebeck coefficient, thermal behavior, and magnetic properties were performed. Band structure calculations were carried out to investigate the electronic structures and the chemical bonding characteristics. These studies have shown that complex Zintl phases exhibit a rich diversity of crystal structures and also shown that the remarkable success of the Zintl concept in rationalizing crystal structure, stoichiometry, and chemical bonding. The measurements of physical properties confirmed that almost Zintl compounds prepared in this research have narrow band-gaps and also have a potential as thermoelectric materials. The work presented in Part Ⅱ describes efforts to synthesize porous materials with functionality and nano-size materials using the face-capped octahedral [Re_(6)Q_(8)(CN)_(6)]^(4-) (Q=Se, Te) clusters. We synthesized two-dimensional framework Mn(salen)]_(4n)[Re_(6)Te_(8)(CN)_(6)]_(n) and three-dimensional framework Na[Mn(salen)]_(3)[Re_(6)Se_(8)(CN)_(6)] (salen=N,N'-ethylenebis(salicylideneaminato)). We found that changing Q in a [Re_(6)Q_(8)(CN)_(6)]^(4-) cluster can control the dimensionality of infinite frameworks. We also synthesized discrete molecules Na[Mn(TPP)(CH_(3)OH)]_(3)[Re_(6)Te_(8)(CN)_(6)] and [Mn(OEP)]_(4)[Re_(6)Te_(8)(CN)_(6)] containing manganese porphyrin complexes instead of extended frameworks. Especially, Na[Mn(TPP)(CH_(3)OH)]_(3)[Re_(6)Te_(8)(CN)_(6)] showed a high catalytic activity in the epoxidation of olefis by iodosylbenzene. We also synthesized another discrete nanomolecular compounds (∼2.5nm), [(CN)_(2)Re_(6)Se_(8){(CN)Fe(Ll)}_(4)] 7H_(2)O and [(CN)_(2)Re_(6)Te_(8){(CN)Fe(L2)}_(4)] 4CH_(3)CN 4H_(2)O [L1=bis(3-salicylideneaminopropyl)amino, L2=bis(3-salicylideneaminopropyl)methylamine]. These studies demonstrate that multinuclear metal clusters are good candidates as building blocks for new heterogeneous catalysts and show the requisite for exploration with a different hexanuclear metal cluster with magnetically susceptible properties as a mediator.;Part I에서는 새로운 Zintl 화합물의 합성과 그 물리적 성질에 관한 연구를 다뤘다. 본 연구는 무거운 원소로 구성되어 있어서 공기 중에서 안정하고, 동시에 복잡한 구조를 가지는 좁은 띠 간격의 반도체인 Zintl 화합물을 합성하여 열전재료로 응용하는데 그 목적을 두고 있다. 이를 위해 무거운 원소로써 알칼리 토금속 또는 희토류 금속을 선택하였고 이를 전이금 속, 13족, 15족 원소들과 결합시켰다. 그 결과로써 공기 중에서 안정한 비등 방성 Zintl 화합물인 Eu_(5)In_(2)Sb_(6), Ba_(3)Ga_(4)Sb_(5), Eu_(7)Ga_(6)Sb_(8), Yb_(9)Zn_(4)Sb_(9), Eu_(10)MN_(6)Sb_(13)과 불안정한 Sr_(2)MnSb_(2), Sr_(11)Cd_(6)Sb_(12) 얻었다. 대부분의 화합물들은 고온에서 원소들의 직접 반응을 통해서 합성되었으며 전이금속을 포함하고 있는 Zintl 화합물의 경우는 Sn flux를 사용하여 합성하였다. 각 화합물의 전기전도도, Seebeck 상수, 자기적 성질을 측정하였고 열분석을 하였다. 또한 전자구조와 화학적 결합상태를 알아보기 위해 띠 구조 계산을 하였다. 이러한 실험 등을 통해서 합성된 Zintl 화합물들이 복잡하고 다양한 구조를 가짐을 규명하였고 결정구조, 화학양론, 화학결합을 이론적으로 합리화하는데 Zintl 개념이 잘 적용됨을 보여주었다. 또한 합성된 대부분의 화합물들은 복잡한 구조와 좁은 띠 간격을 가지는 반도체로써 열전재료로의 가능성을 보여주었다. Part Ⅱ에서는 [Re_(6)Q_(8)(CN)_(6)]^(4-) (Q=Se,Te) 클러스터를 이용하여 기능성을 가진 다공성 물질과 나노 크기의 물질의 합성과 그 성질에 관한 연구를 하였다. 사용하는 칼코겐 클러스터 따라 구조의 차원이 달라짐을 보였다. Mn(Salen)]_(4n)[Re_(6)Te_(8)(CN)_(6)]_(n) 화합물은 2차원 구조를, Na[Mn(Salen)]_(3)[Re_(6)Se_(8)(CN)_(6)] (salen=N,N'-ethylenebis(salicylideneaminato)은 3차원 구조를 가졌다. Mn-porphyrin 화합물을 클러스터에 연결한 경우 무한히 연결된 구조가 아닌 분자구조의 Na[Mn(TPP)(CH_(3)OH)]_(3)[Re_(6)Te_(8)(CN)_(6)]와 [Mn(OEP)]_(4)[Re_(6)Te_(8)(CN)_(6)]를 합성하였다. 특히 Na[Mn(TPP)(CH_(3)PH)]_(3)[Re_(6)Te_(8)(CN)_(6)] 화합물은 올레핀의 에폭시화 반응에 있어서 탁월한 촉매효과를 보였다. 5배위 리간드를 가지고 있는 철 화합물을 클러스터에 연결시킨 결과 약 ∼2.5Mnm 크기의 [(CN)_(2)Re_(6)Se_(8){(CN)Fe(L1)}_(4)] 7H_(2)O 와 [(CN)_(2)Re_(6)Te_(8){ (CN)Fe(L2)}_(4)] 4CH_(3),CN 4H_(2)O [L1= bis(3-salicylideneaminopropyl)amine, L2= bis(3-salicylideneaminopropyl)methylamine] 화합물을 합성하였다. 이 연구들을 통해서 다핵의 금속 클러스터가 새로운 불균일 촉매로써의 훌륭한 재료임을 보여주었고 자기적 성질 연구를 통해서는 다른 금속과의 중재자로써 새로운 클러스터에 대한 필요성을 제시하였다.-
dc.description.tableofcontentsContents = ⅲ List of Figures = ⅵ List of Tables = ⅹⅰ Abstract = ⅹⅴ Part Ⅰ. Synthesis and Characterization of New Zintl compounds = 1 Chapter 1 Introduction = 2 1.1. Introduction to Zintl phases = 2 1.2. Zintl phase for new thermoelectric materials = 4 Chapter 2 Experimental = 15 2.1. Starting Materials and Synthesis = 15 2.2. Characterization Techniques = 18 Chapter 3 Main Group Zintl Compounds = 25 3.1. Introduction = 25 3.2. Eu_(5)IN_(2)Sb_(6), Eu_(5)In_(2-x)Zn_(x)Sb_(6) : A Rare Earth Zintl Phases with a Narrow Band Gap = 27 3.2.1. Experimental = 27 3.2.2. Results and Discussion = 33 3.2.3. Conclusion = 44 3.3. Ba_(3)Ga_(4)Sb_(5) : Ga-Ga Bonding and Tunnel Framework in the New Zintl Phase = 45 3.3.1. Experimental Section = 45 3.3.2. Results and Discussion = 51 3.3.3. Conclusion = 59 3.4. Eu_(7)Ga_(6)Sb_(8) : A New Zintl Phase with Ga-Ga Bonds and Polymeric Gallium Antimonide Chains = 60 3.4.1. Experimental = 60 3.4.2. Results and Discussion = 69 3.4.3. Conclusion = 80 Chapter 4 Transition Metal Zintl Compounds = 85 4.1. Introduction = 85 4.2. Mixed valence of Yb in Yb_(9)Zn_(4)Sb_(9) = 87 4.2.1. Experimental Section = 87 4.2.2. Results and Discussion = 94 4.2.3. Conclusion = 99 4.3. Eu_(10)Mn_(6)Sb_(13) : A New Ternary Rare-Earth Transition Metal Zintl Phase = 100 4.3.1. Experimental Section = 100 4.3.2. Results and Discussion = 108 4.3.3. Conclusion = 116 4.4. Sr_(2)MnSb_(2) : A New Ternary Transition Metal Zintl Phase = 118 4.4.1. Experimental = 118 4.4.2. Results & Discussions = 124 4.4.3. Conclusion = 129 4.5. Sr_(11)Cd_(6)Sb_(12) : A New Ternary Transition Metal Zintl Phase = 130 4.5.1. Experimental = 130 4.5.2. Results and Discussion = 136 4.5.3. Conclusion = 140 Part Ⅱ. Synthesis and Characterization of Re_(6) Cluster-containing Compounds = 145 Chapter 1 Introduction = 146 Chapter 2 Dimensionality Control by Using Different Chalcogen Ligand in [Re_(6)Q_(8)]^(2+)Cluster = 157 2.1. Introduction = 157 2.2. Experimental = 158 2.3. Results and Discussion = 164 2.4. Conclusion = 173 Chapter 3 Synthesis and Reactivity of Rhenium Cluster-supported Manganese Porphyrin Complexes = 174 3.1. Introduction = 174 3.2. Experimental = 177 3.3. Results and Discussion = 194 3.4. Conclusion = 201 Chapter 4. Synthesis and Structures of Nanosize Molecules = 203 4.1. Introduction = 203 4.2. Experimental = 204 4.3. Results and Discussion = 216 4.4. Conclusion = 220 국문초록 = 227 감사의 글 = 229-
dc.format.extent7651589 bytes-
dc.publisher이화여자대학교 대학원-
dc.subjectzintl compounds-
dc.subjectcluster-containing complexes-
dc.titleSynthesis and characterization of new zintl compounds and Re_6 cluster-containing complexes-
dc.typeDoctoral Thesis-
dc.format.pagexvi, 230 p.-
dc.identifier.major대학원 나노과학부- 8-
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