The elastic constants, phase stability, heat of formation and the Debye temperature of various noble metal compounds in the stoichiometry A3B (where A = Pt, Ir, Rh, Ru, Pd and B = Al, Hf, Zr, Sc) were studied using the ab initio Density Functional Theory - Projector Augmented Wave method. A total of 24 compositions was investigated, of which 16 compounds were predicted to be thermodynamically stable. The remaining eight compounds were found not energetically favorable, due to positive or low heats of formation. According to the Density of States studies, the L12 structure was predicted in 8 compounds while four compounds had the D024 structure. Among compounds with the L12 structure, the hardest phase predicted was L12-Ir3Hf. L12-Pd3Sc was predicted as the least hard and most ductile compound. In compounds with the D024 structure, Pt3Zr was predicted having highest hardness and highest melting point. In all the compounds, the strongest interaction was found between hafnium and the noble metals and least interaction was with aluminum. The melting points from ab initio and molecular dynamics calculations slightly over-predicted experimental values, but showed the same trends. Both the fracture toughnesses and the melting points deduced using the Sutton-Chen potentials had similar trends to ab initio results, suggesting that the Sutton-Chen potentials is adequate for simulating metallic phases.

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Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.

Epithermal deposits include a broad range of precious metal, base metal, mercury, and stibnite deposits. These deposits exhibit a low temperature of formation (180-280°C) at pressures of less than a few hundred bars (equivalent to depths of 1.5 - 2.0lkm). Epithermal gold deposits are the product of large-scale hydrothermal systems which mostly occur in convergent plate margin settings. Associated volcanism is largely of andesitic arc (calcalkaline to alkaline), or rhyolitic back-arc type. Porphyry Cu-Mo-Au deposits form deeper in the same systems. Genetic processes within individual deposits take place in an extremely complex manner. The resultant mineral associations, alteration styles and metal deposition patterns are even more complicated. Many attempts have been made to classify epithermal deposits based on mineralogy and alteration, host rocks, deposit form, genetic models, and standard deposits. For the explorationist, the most useful classification schemes should be brief, simple, descriptive, observationally based, and informative. Ultimately, two distinct styles of epithermal gold deposits are readily recognised: high-sulphidation, acid sulphate and low-sulphidation, adularia-sericite types. The terms high-sulphidation (HS) and low-sulphidation (IS) are based on the sulphidation state of associated sulphide minerals, which, along with characteristic hydrothermal alteration, reflect fundamental chemical differences in the epithermal environment. Highsulphidation-type deposits form in the root zones of volcanic domes from acid waters that contain residual magmatic volatiles. The low-sulphidation-type deposits form in geothermal systems where surficial waters mix with deeper, heated saline waters in a lateral flow regime, where neutral to weakly acidic, alkali chloride waters are dominant. The HSILS classification, combined with a simple description of the form of the deposit, conveys a large amount of information on mineralogy, alteration, and spatial characteristics of the mineralisation, and allows inferences to be drawn regarding likely regional controls, and the characteristics of the ore-forming fluids. The modern understanding of these environments allows us to quite effectively identify the most probable foci of mineral deposition in any given district. Current knowledge of these deposits has been derived from studies of active geothermal systems. Through comparison with alteration zones within these systems, the exploration geologist may determine the potential distribution and types of ore in a fossil geothermal system. Alteration zoning specifically can be used as a guide towards the most prospective part of the system. Epithermal gold deposits of both HS- and LS-styles are nevertheless profoundly difficult exploration targets. Successful exploration must rely on the integration of a variety of exploration techniques, guided by an understanding of the characteristics of the deposits and the processes that form them. There are no simple formulae for success in epithermal exploration: what works best must be determined for each terrain and each prospect. On a regional scale tectonic, igneous and structural settings can be used, together with assessment of the depth of erosion, to select areas for project area scale exploration. Integrated geological-geophysical interpretation derived from airborne geophysics providesa basis of targeting potential ore environments for follow-up. Geology, geochemistry and surface geophysics localise mineral concentrations within these target areas

共振是自然界一個基本物理過程。特別是，在納米尺度上的光頻電磁諧振產生顯著的場增強，提供了一種手段來影響和控制光與物質的相互作用。例如，巨大的場增強使表面增強拉曼散射具有探測單個分子的靈敏度。此外，場增強可以使發光二極體具有更高亮度高，但輸入功率更低。雖然場增強在一些關鍵技術領域大有前途，有許多挑戰仍有待解決。由於場增強是如此強烈地依賴系統的幾可形狀即使稍作修改可以導致大的結果變化，因此理解幾何結構如何影響場增強和可重複的製造這些車前壽是最重要的。因此本論文致力於設計，製造和貴金屬如銀或金的一維結構的表面上生成的場增強特性。 / 首先對s-偏振下一維金屬光栅產生的場增強使用嚴格購合波分析(RCWA) 進行了設計和優化。優化後，在514nm 波長最強的增強因數是9.7 。製作了一維光栅並進行角度相關的反射率測量，實驗結果與理論計算相符。 / 對一種新型利用表面等離子激元的呻吟加強電場的單縫桔構進行了研究。首先利用用衰減全反射搞合在50 納米厚的金屬薄膜上產生sp恥，隨後利用spps 驅動這一狹縫。結果發現縫內場增強至少3 倍於狹縫附近的等離子激元背景。其增強機理用數值和分析的方法進行理論研究。 / 提出了兩種新型的製造高深寬比納米縫隙的簡便方法。一個是在飯有金膜的薄玻璃上製造裂紋，獲得了寬度小於5nm 具有一定平整度的抗縫，通過掃描電子顯微鏡圖像和共焦雙光子發射(CTPE) 光譜和時間域有限差分模擬的對比得到了確認。另一種是對鍍有金膜的柔性基底進行疲勞彎折，獲得了大量狹縫。觀察到CTPE 和二次諧波產生從這些縫中產生。 / 採用電子束光刻製作了納米縫並使用CTPE 進行了表徵。提出一種新方法對激發波長和發射波長的增強因數進行了分解。發現脈衝錯射能調整EBL 樣品的共振波長到錯射波長。提出了一種機制解釋這一現像。進一步實驗表明這是一種製造任意共振波長場增強熱點的有用方法。 / Resonance may be one of the most fundamental rules of nature. Electromagnetic resonance at nanometer scale could produce a giant field enhancement at optical frequency, providing a way to measure and control the process of atoms and molecules at single molecule scale. For example, the giant field enhancement would provide single molecule sensitivity for Raman scattering, which provides unique tools in measuring the quantity in extremely low concentration. In addition, light-emitting diodes could have high brightness but low input power that would be revolutionary in the optoelectronic industry. Although light enhancement is promising in several key technology areas, there are several challenges remain to be tackled. In particular, since the field enhancement is so strongly geometry dependent that slight modification of the geometry can lead to large variations in the outcome, a thorough understanding in how the geometry of the structure affects the field enhancement and creating proper methods to fabricate these structures reproducibly is of most importance. This thesis is devoted to design, fabrication and characterization of field enhancement generated on the surface of noble metals such as silver or gold with 1D structure. / The s-polarized field enhancement arISIng from one-dimensional metal gratings IS designed and optimized by using Rigorous Coupling Wave Analysis (RCWA). After optimization, the strongest enhancement factor is found to be 9.7 for 514nm wavelength light. The theoretical results are confirmed by angle-dependent reflectivity measurements and the experimental results are found to support the theory. / A novel single slit structure employing sUlface plasmon polaritons (SPPs) for enhancing the electric field is studied. SPPs are first generated on a 50 nm thick metal film using attenuated total reflection coupling, and they are subsequently coupled to the cavity mode induced by the single slit. As a result, the field enhancement is found at least 3 times the surface plasmon background adjacent to the slit, as predicted by using RCWA. The mechanism for enhancement is theoretically studied both numerically and analytically. / Two novel convenient methods for fabricating nanoslits with high aspect ratio are proposed. One is creating nanoslits by cracking the thin glass substrates with metal film. Sub-Snm wide slits with fair uniformity are created, as confirmed by Scanning Electron Microscopy images and comparing the Confocal Two Photon Emission (CTPE) spectroscopy with finite difference in time domain simulations. The other is creating slits by fatiguing the metal film on a flexible substrate. Enhanced CTPE and second harmonic generation are observed arising from these less than 20nm wide slits. / Nanoslits fabricated using Electron Beam Lithography (EBL) are characterized using CTPE. The overall emission enhancement of excitation and collection wavelengths is separated by a proposed method. It is surprisingly found that the pulsing laser can tune the resonant wavelength of the EBL samples to the laser wavelength. A mechanism is proposed for this phenomenon. It is shown this can be developed into a tool to fabricate field enhancement hot spots. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Liu, Benliang = 用貴金屬結構增強場強 / 劉本良. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 133-137). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Liu, Benliang = Yong gui jin shu jie gou zeng qiang chang qiang / Liu Benliang. / Acknowledgement --- p.i / Abstract --- p.ii / 摘要 --- p.iv / List of figures --- p.1 / Chapter 1 --- Overview --- p.1 / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.2 --- Applications of field enhancement --- p.1 / Chapter 1.2.1 --- Surface enhanced Raman scattering --- p.1 / Chapter 1.2.2 --- Enhanced luminescence --- p.4 / Chapter 1.3 --- Fundamentals of field enhancement --- p.5 / Chapter 1.3.1 --- The Maxwell's equations --- p.6 / Chapter 1.3.2 --- Boundary conditions --- p.8 / Chapter 1.3.3 --- Phase matching condition --- p.10 / Chapter 1.3.4 --- Dipole --- p.11 / Chapter 1.3.5 --- Purcell factor --- p.12 / Chapter 1.3.6 --- Mode and mode interaction --- p.13 / Chapter 1.3.7 --- Surface plasmon resonance --- p.14 / Chapter 1.3.8 --- Fabry-Perot cavity resonance --- p.16 / Chapter 1.4 --- Overview of the nanofabrication methods of metal structures for field enhancement --- p.17 / Chapter 1.4.1 --- Photolithography --- p.18 / Chapter 1.4.2 --- Electron Beam Lithography --- p.20 / Chapter 1.4.3 --- Focused ion beam --- p.21 / Chapter 1.4.4 --- Summary --- p.21 / Chapter 2 --- Methods of simulation --- p.26 / Chapter 2.1 --- Rigorous coupled wave analysis framework --- p.26 / Chapter 2.1.1 --- FormulaofRCWA --- p.26 / Chapter 2.1.2 --- Expression ofMaxwell's equations in Fourier space --- p.27 / Chapter 2.1.3 --- Numerical shooting method --- p.29 / Chapter 2.1.4 --- Reflection efficiency, transmission efficiency and absorption --- p.32 / Chapter 2.1.5 --- Convergence test of the RCWA simulation --- p.33 / Chapter 2.2 --- Finite difference in time domain --- p.34 / Chapter 2.2.1 --- Formulations of FDTD --- p.34 / Chapter 2.2.2 --- Dispersion of dielectric constant --- p.35 / Chapter 2.2.3 --- Boundary conditions and excitation sources --- p.37 / Chapter 3 --- Investigation of s-polarized resonance on 1D grating --- p.40 / Chapter 3.1 --- Introduction --- p.40 / Chapter 3.2 --- Theoretical results of the s-polarized resonance in the 1D grating --- p.41 / Chapter 3.3 --- Discussion of the theoretical results --- p.47 / Chapter 3.3.1 --- Origination of the s-polarized resonance modes --- p.47 / Chapter 3.3.2 --- Position discrepancy between absorption peaks and reflection dips --- p.48 / Chapter 3.3.3 --- Absorption beyond the cutoff wavelength of reflectance --- p.48 / Chapter 3.3.4 --- Absorption wavelength dependency on the periodicity --- p.50 / Chapter 3.4 --- Effects of parameters on absorption and electric field --- p.50 / Chapter 3.5 --- Optimization the s-polarized resonance for field enhancement --- p.54 / Chapter 3.6 --- Angle dependency of the optimized resonant mode --- p.55 / Chapter 3.7 --- Grating preparation and characterization --- p.57 / Chapter 3.8 --- Experimental results and discussion --- p.59 / Chapter 3.9 --- Summary --- p.73 / Reference --- p.74 / Chapter 4 --- Fabricating and characterizing nanoslit-shaped resonant cavity --- p.75 / Chapter 4.1 --- Introduction --- p.75 / Chapter 4.2 --- Confocal two photon emission measurement --- p.78 / Chapter 4.2.1 --- Background --- p.78 / Chapter 4.2.2 --- Polarization dependence of the confocal system --- p.79 / Chapter 4.3 --- Decomposition of excitation and collection TPL enhancement --- p.81 / Chapter 4.4 --- Fabrication and characterization of slits by cracking glass substrate --- p.83 / Chapter 4.4.1 --- Fabrication of nanoslits by cracking glass --- p.83 / Chapter 4.4.2 --- Characterization of the nanoslits by cracking glass substrates --- p.86 / Chapter 4.4.2.1 --- Two-photon emission from rough slits 86 / Chapter 4.4.2.2 --- Location dependence of the two-photon emission --- p.87 / Chapter 4.4.2.3 --- Relation between reflection and two-photon emission --- p.88 / Chapter 4.4.2.4 --- Wavelength dependence ofTPLfrom the slits by cracking glass --- p.89 / Chapter 4.4.3 --- Discussion --- p.97 / Chapter 4.4.4 --- Summary --- p.98 / Chapter 4.5 --- Fabrication and characterization of nanoslits by fatigue --- p.98 / Chapter 4.5.1 --- Fabrication ofnanoslits by fatigue --- p.98 / Chapter 4.5.2 --- Characterization ofnanoslits by fatigue --- p.100 / Chapter 4.5.3 --- Discussion --- p.105 / Chapter 4.6 --- Two photon emission from nanoslits by EBL --- p.106 / Chapter 4.6.1 --- Sample preparation --- p.107 / Chapter 4.6.2 --- Characterization of the slits made by Electron Beam Lithography --- p.109 / Chapter 4.6.2.1 --- Reflected light extinction and two photon emission --- p.109 / Chapter 4.6.2.2 --- Wavelength dependence of TPL enhancement --- p.120 / Chapter 4.6.2.3 --- Laser modification of resonant wavelength of the cavity --- p.124 / Chapter 4.6.2.4 --- Discussion --- p.126 / Chapter 4.6.3 --- Summary --- p.132 / Chapter 5 --- Conclusion --- p.138

Thesis (Ph.D.)(Metallurgical Engineering)--University of Pretoria, 2005. / Includes summary. Includes bibliographical references.

Thesis (Ph. D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2005. / Wang, Zhong Lin, Committee Member ; Whetten, Robert L., Committee Member ; El-Sayed, Mostafa A., Committee Member ; Dickson, Robert M., Committee Chair ; Lyon, Andrew L., Committee Member.

Woo, Kat Choi = 以時域有限差分法模擬貴金屬的納米結構 / 胡吉才. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 84-86). / Abstracts in English and Chinese. / Woo, Kat Choi = Yi shi yu you xian cha fen fa mo ni gui jin shu de na mi jie gou / Hu Jicai. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- The Importance of Nanoscale Plasmonic Physics --- p.1 / Chapter 1.2 --- The Driving Forces behind Plasmon Physics --- p.2 / Chapter 1.3 --- Computation Method --- p.3 / Chapter 1.4 --- Conclusion and Interesting Topics --- p.5 / Chapter 2 --- The FDTD Mechanism --- p.6 / Chapter 2.1 --- Algorithm Method --- p.6 / Chapter 2.2 --- The Dielectric Function --- p.9 / Chapter 2.2.1 --- Drude Model Definition --- p.9 / Chapter 2.2.2 --- Drude Model Discretization --- p.10 / Chapter 2.2.3 --- Discussion on Models --- p.11 / Chapter 2.3 --- Accuracy and Stability --- p.12 / Chapter 2.3.1 --- Numerical Dispersion --- p.12 / Chapter 2.3.2 --- Courant Condition --- p.14 / Chapter 2.4 --- Time Dependence of the Methods --- p.15 / Chapter 2.5 --- Perfectly Matched Layer (PML) --- p.16 / Chapter 2.5.1 --- Boundaries Problem --- p.16 / Chapter 2.5.2 --- PML Main Theme --- p.17 / Chapter 2.5.3 --- Different Types of PMLs --- p.20 / Chapter 2.6 --- Conclusion: Simulation Laboratory --- p.20 / Chapter 3 --- Software Comparison and Scaling Usage --- p.22 / Chapter 3.1 --- Physical Quantity Interested --- p.22 / Chapter 3.1.1 --- Cross-sections and Relation to Surface Plasmon Excitation --- p.23 / Chapter 3.2 --- Mie Theory --- p.24 / Chapter 3.2.1 --- Spherical Harmonics --- p.24 / Chapter 3.2.2 --- Expressing the terms in Spherical Harmonics --- p.26 / Chapter 3.2.3 --- Matching Boundaries --- p.27 / Chapter 3.2.4 --- Scattering and Extinction Cross-sections --- p.28 / Chapter 3.3 --- Software Used --- p.29 / Chapter 3.3.1 --- Meep --- p.29 / Chapter 3.3.2 --- Lumerical FDTD Solution --- p.30 / Chapter 3.4 --- Machines Used for Comparison --- p.30 / Chapter 3.5 --- Ease of Usage --- p.30 / Chapter 3.5.1 --- Installation --- p.31 / Chapter 3.5.2 --- Support --- p.32 / Chapter 3.5.3 --- Parallel Computation --- p.33 / Chapter 3.6 --- The Check Case Building --- p.33 / Chapter 3.6.1 --- Monitor Measurement Related to Time for Simulation --- p.34 / Chapter 3.6.2 --- Meep's Implementation --- p.34 / Chapter 3.6.3 --- Total Field Scattering Field (TFSF) Source --- p.35 / Chapter 3.6.4 --- Lumerical FDTD Solutions' Implement at ion --- p.36 / Chapter 3.7 --- Comparison --- p.37 / Chapter 3.7.1 --- Accuracy of the Programs --- p.37 / Chapter 3.7.2 --- Time Needed for the Programs --- p.43 / Chapter 3.8 --- Conclusion: How to Build Reasonable Running Cases --- p.46 / Chapter 4 --- The Projects on Nanorods --- p.47 / Chapter 4.1 --- Basic Understanding of Nanorods --- p.47 / Chapter 4.1.1 --- Geometry Dependence on Localized Surface Plasmon Resonance in Au Nanorods --- p.48 / Chapter 4.1.2 --- Plasmonic Coupling in Au Nanorod Dimers --- p.49 / Chapter 4.2 --- Size-Dependent Scattering and Absorption Cross-sections for Au Nanocrystals --- p.51 / Chapter 4.2.1 --- Measurement of Data --- p.51 / Chapter 4.2.2 --- Setup of Simulation --- p.52 / Chapter 4.2.3 --- Results and Conclusion --- p.54 / Chapter 4.3 --- Angle-Dependent Plasmon Coupling in Au Nanorod Dimers --- p.56 / Chapter 4.3.1 --- Setup of Experiment --- p.56 / Chapter 4.3.2 --- Setup of Simulation --- p.57 / Chapter 4.3.3 --- Results of Simulation --- p.59 / Chapter 4.3.4 --- The Dipolar Model Discussion --- p.62 / Chapter 4.3.5 --- Conclusion --- p.65 / Chapter 4.4 --- Plasmon Coupling in Linear Au Nanorod Dimers --- p.65 / Chapter 4.4.1 --- Experimental Results --- p.66 / Chapter 4.4.2 --- Energy Dependent Plasmon Coupling of Au Nanorod Dimers --- p.67 / Chapter 4.4.3 --- Dependency of the Plasmon Coupling on the Inter-particle Distance --- p.70 / Chapter 4.4.4 --- Dependency of the Plasmon Coupling on the Head Shape of Au Nanocrystals --- p.74 / Chapter 4.4.5 --- Coupling-induced Fano-Resonance in Au Nanorod Het- erodimers --- p.74 / Chapter 4.4.6 --- Conclusion --- p.78 / Chapter 4.5 --- Conclusion --- p.80 / Chapter 5 --- Conclusion --- p.81 / Bibliography --- p.84

published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy