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Studies on the Synthesis and Structural Characterizations of the New Transition Metal Chalcogenides

  • 윤우진 (Yoon Woojin, 아주대학교 일반대학원)

초록/요약

PART 1. Two-Step Hybrid Synthesis The new quaternary alkali-metal chromium thiophosphates, ACr3P2S10, ACrPS5, and A2CrPS6 (A = Rb, Cs) have been synthesized by solid-state reaction of pure elemental powders with reactive halide fluxes at high temperature (First step). The crystal structures have been determined by single crystal X-ray diffraction techniques. The title compounds have octahedral CrS6 and tetrahedral PS4 as basic building units. These units are linked by edge sharing S atoms to form anionic species, _∞^( 2)[Cr3P2S10-] layers, _∞^( 1)[CrPS5-] chains, and _∞^( 0)[CrPS62-] isolated clusters. Of these, ACrPS5 and A2CrPS6 consist of Cr2P2S12x-, the anionic binuclear cluster formed by two pairs of units sharing edges. These anionic chromium thiophosphates and alkali metal cations, A+ are bound through ionic interactions stabilizing the overall structure. The charge valences derived from the structure of ACr3P2S10, ACrPS5, and A2CrPS6 can be described as [A+][Cr3+]3[P5+]2[S2-]10, [A+][Cr4+][P5+][S2-]5, and [A+]2[Cr5+][P5+][S2-]6, respectively. To the best of our knowledge, ACrPS5 and A2CrPS6 are the first examples of the tetravalent and pentavalent Cr ion in thiophosphates. In the second step, these alkali-metal chromium thiophosphates prepared through solid-state reactions were dissolved in polar solvents such as water, NMF, and DMF and new ionic species were found through ion exchanges. The precursor, Cs2CrPS6 was dissolved in water and PPh4Cl was added to replace the Cs+ ion. As a result, a new compound, Cr2P2S8(H2O)4·2PPh4Cl·10H2O was isolated as single crystals. The crystal structure of this compound has been determined by single crystal X-ray diffraction techniques. In the precursor Cs2CrPS6, the terminal S atoms of CrS6 octahedra was replaced by the oxygen atoms of the water molecule to form a new neutral binuclear cluster, Cr2P2S8(H2O)4. These clusters are infinitely connected through hydrogen bonds with crystal waters and Cl- ions in the direction parallel to the ac-plane to form the layers. Between these layers, PPh4+ cations are located, completing the three-dimensional structure. The charge valences of this compound can be described as [PPh4+]2[Cr3+]2[P5+]2[S2-]8[Cl-]2[H2O]14 and oxidation state of the Cr ion in the precursor is reduced from +5 to +3.   PART 2. New Hexanary Phases The new hexanary two-dimensional niobium(V) thiochlorophosphates, ANbPO4SCl (A = K, Rb, Cs) have been synthesized through reactive alkali metal halide flux methods and structurally characterized by single crystal X-ray diffraction techniques. They are isostructural and they crystallize in the space group P4/nmm of the tetragonal system. Each niobium atom is surrounded by one chlorine, one sulfur, and four oxygen atoms in the distorted octahedral fashion and phosphorus atom is coordinated by four oxygen in a tetrahedral geometry. These polyhedra are combined to form the two-dimensional infinite anionic layers, _∞^( 2)[NbPO4SCl-]. Alkali metal ions reside between the layers to stabilize the three-dimensional structures. To the best of our knowledge, the octahedral coordination around Nb in this phase NbO4SCl is the first example that has not yet been reported. In addition, pentanary, ANbPO5Cl and non-stoichiometric hexanary, ANbPO4SexO(1-x)Cl (A = Rb, Cs) were synthesized through additional experiments and their structure were analyzed. The classically charged valences of these phases can be described as [A+][Nb5+][P5+][O2-]4[S2-][Cl-], [A+][Nb5+][P5+][O2-]5[Cl-], and [A+][Nb5+][P5+][O2-]4[Se2-]x[O2-](1-x)[Cl-]. In this work, we discuss the nature of bonds around the Nb atoms based on bond valence analysis.

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목차

PART 1. Two-Step Hybrid Synthesis 1
I. INTRODUCTION 2
II. First step: Synthesis and Structural Characterizations of the New Quaternary Alkali-metal Chromium Thiophosphates, ACr3P2S10, ACrPS5, and A2CrPS6 (A = Rb, Cs) 5
2.1. EXPERIMENTAL 5
2.1.1. Synthesis. 5
2.1.2. Crystallographic Studies. 7
2.1.3. UV/Vis spectroscopy. 15
2.1.4. X-ray photoelectron spectroscopy (XPS). 16
2.1.5. Solubilization. 17
2.2. RESULT AND DISCUSSION 18
2.2.1. XPS results of various chromium thiophosphate compounds. 23
III. Second step: Synthesis and Structural Characterization of the New Chromium(III) Thiophosphate Cluster 31
3.1. EXPERIMENTAL 31
3.1.1. Synthesis. 31
3.1.2. Crystallographic Studies. 31
3.2. RESULT AND DISCUSSION 33
IV. REFERENCES 40
PART 2. New Hexanary Phases 42
I. INTRODUCTION 43
II. Synthesis and Crystal Structure of the New Hexanary Niobium(V) Thiochlorophosphates, ANbPO4SCl (A = K, Rb, Cs) 46
2.1. EXPERIMENTAL 46
2.1.1. Synthesis. 46
2.1.2. Crystallographic Studies. 47
2.2. RESULT AND DISCUSSION 50
III. Synthesis and Structures of the New Pentanary, ANbPO5Cl and Non-stoichiometric Hexanary, ANbPO4SexO(1-x)Cl (A = Rb, Cs) 57
3.1. EXPERIMENTAL 57
3.1.1. Synthesis. 57
3.1.2. Crystallographic Studies. 58
3.2. RESULT AND DISCUSSION 64
IV. REFERENCES 69
PART 3. Appendix 70
Chapter 1. The mixed-metal tris(disulfide) thiophosphate, KNb1.77Ta0.23PS10 71
1.1. ABSTRACT 71
1.2. RELATED LITERATURE 71
1.3. EXPERIMENTAL 71
1.3.1. Crystal data 71
1.3.2. Data collection 71
1.3.3. Refinement 72
1.4. REFERENCES 75
Chapter 2. Synthesis and Crystal Structure of the New One-Dimensional Quaternary Tantalum Thiophosphate, Cs3Ta2PS12 76
2.1. ABSTRACT 76
2.2. INTRODUCTION 76
2.3. EXPERIMENTAL 77
2.3.1. Synthesis. 77
2.3.2. Crystallographic Studies. 77
2.3.3. Solid-State UV/Vis Spectroscopy. 79
2.3.4. Acknowledgments. 79
2.3.5. Supporting Information. 79
2.4. RESULT AND DISCUSSION 80
2.5. REFERENCES 85
Chapter 3. Synthesis and Crystal Structure of the New Mixed-metal Bismuth Indium Sulfide, Bi0.76In1.24S3 86
3.1. ABSTRACT 86
3.2. INTRODUCTION 86
3.3. EXPERIMENTAL 87
3.3.1. Synthesis. 87
3.3.2. Crystallographic Studies. 88
3.3.3. Supporting Information. 88
3.3.4. Solid-State UV/Vis Spectroscopy. 88
3.4. RESULT AND DISCUSSION 90
3.4.1. Crystal Structure. 90
3.4.2. Optical Properties. 93
3.5. REFERENCES 94
Chapter 4. Synthesis and Crystal Structure of the New One-Dimensional Ternary Niobium Sulfide Chloride, Nb24S95Cl7 95
4.1. ABSTRACT 95
4.2. INTRODUCTION 95
4.3. EXPERIMENTAL 96
4.3.1. Synthesis. 96
4.3.2. Crystallographic Studies. 96
4.3.3. Solid-State UV/Vis Spectroscopy. 97
4.3.4. Supporting Information. 97
4.4. RESULT AND DISCUSSION 99
4.5. REFERENCES 104
Chapter 5. Synthesis and Structure of a New Two-dimensional Thiophosphate, AgTiPS6 105
5.1. ABSTRACT 105
5.2. INTRODUCTION 105
5.3. EXPERIMENTAL 106
5.3.1. Synthesis. 106
5.3.2. Crystallographic Studies. 106
5.3.3. Supporting Information. 107
5.4. RESULT AND DISCUSSION 109
5.5. REFERENCES 113
Chapter 6. Synthesis and Structure of a New One-dimensional Chromium Thiophosphate Chloride, Ag2Rb2Cr2(PS4)3Cl 114
6.1. INTRODUCTION 114
6.2. EXPERIMENTAL 115
6.2.1. Synthesis. 115
6.2.2. Crystallographic Studies. 115
6.3. RESULT AND DISCUSSION 118
6.4. REFERENCES 122
Chapter 7. Synthesis and Structure of a New Pentanary One-Dimensional Palladium Thiophosphate, K2PdPS4I 123
7.1. ABSTRACT 123
7.2. INTRODUCTION 123
7.3. EXPERIMENTAL 125
7.3.1. Synthesis. 125
7.3.2. Crystallographic Studies. 125
7.4. RESULT AND DISCUSSION 128
7.5. CONCLUSION 132
7.6. REFERENCES 133
Chapter 8. Crystal Structure of Vanadium(III) Silicophosphate, VP3SiO11 135
8.1. ABSTRACT 135
8.2. SOURCE OF MATERIAL 135
8.3. EXPERIMENTAL DETAILS 136
8.4. DISCUSSION 137
8.5. REFERENCES 139
Chapter 9. Synthesis and Structure of New Two-Dimensional Group 4 Metal Palladium Sulfides, A2MPd3S6 (A = Rb, M = Hf; A = Cs, M = Zr, Hf) 140
9.1. ABSTRACT 140
9.2. INTRODUCTION 140
9.3. EXPERIMENTAL 141
9.3.1. Synthesis. 141
9.3.2. Crystallographic Studies. 142
9.4. RESULT AND DISCUSSION 145
9.5. CONCLUSION 149
9.6. ACKNOWLEDGEMENTS 149
9.7. REFERENCES 150
PART 4. List of Publications 151
I. PUBLICATION LIST 152
II. REFERENCES 155

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