Download or read book Quantum Mechanical Models of Metal Surfaces and Nanoparticles written by Wolfgang Gräfe and published by Springer. This book was released on 2015-06-24 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book proposes two simple quantum mechanical models for the analytical description of metal surfaces and nanoparticles. It gives an ostensive picture of the forces acting in a metal surface and deduces analytical formulae for the description of their physical properties. This book explains the relation between near-surface stress and familiar surface parameters. The concept of the separation of the three-dimensional body into three one-dimensional subsystems was applied. The content is of interest to all those working in the field of surface physics.
Download or read book Quantum Mechanical Origin of the Plasmonic Properties of Noble Metal Nanoparticles written by Emilie Brigitte Guidez and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Small silver and gold clusters (
Download or read book Quantum Mechanics for Nanostructures written by Vladimir Vasilʹevich Mitin and published by Cambridge University Press. This book was released on 2010-05-20 with total page 449 pages. Available in PDF, EPUB and Kindle. Book excerpt: Textbook introducing engineers to quantum mechanics and nanostructures, covering the fundamentals and applications to nanoscale materials and nanodevices.
Download or read book Nanostructures written by Christophe Jean Delerue and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 313 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides the theoretical background needed by physicists, engineers and students to simulate nano-devices, semiconductor quantum dots and molecular devices. It presents in a unified way the theoretical concepts, the more recent semi-empirical and ab initio methods, and their application to experiments. The topics include quantum confinement, dielectric and optical properties, non-radiative processes, defects and impurities, and quantum transport. This guidebook not only provides newcomers with an accessible overview (requiring only basic knowledge of quantum mechanics and solid-state physics) but also provides active researchers with practical simulation tools.
Download or read book Modeling Catalytic Properties of Metal Nanoparticles written by Lin Li and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Catalysts are materials that can accelerate chemical reactions, and they are key to creating sustainable processes and a greener environment. Catalysts in the form of metal nanoparticles are ubiquitous in current industrial processes, and they are critical to creating a sustainable energy future. Theory has provided vital insights into the fundamental limitations of various types of processes, and density functional theory (DFT) calculations have inspired the discovery of new active materials. Advancements in supercomputing resources and scalable quantum chemistry codes have enabled us to explore the catalytic behavior of metal nanoparticles from the fundamental atomic level. We present calculated adsorption energies of oxygen on gold and platinum clusters with up to 923 atoms (3 nm diameter) using Density Functional Theory. We find that surface tension of the clusters induces a compression of which weakens the bonding of adsorbates compared to the bonding on extended surfaces. The effect is largest for close packed surfaces and almost non-existent on the more reactive steps and edges. The effect is largest at low coverage and decreases, even changing sign, at higher coverages where the strain changes from compressive to tensile. Quantum-size-effects also influence adsorption energies but only below a critical size of 1.5 nm for platinum and 2.5 nm for gold. We develop a model to describe the strain-induced size effects on adsorption energies, which is able to describe the influence of surface structure, adsorbate, metal, and coverage. Stability of metal nanoparticle is also a great concern in the field of heterogeneous, and a dominant process that degrades the activity of these catalysts is the agglomeration of individual nanoparticles. In order to better understand the sintering mechanism, we propose a kinetic Monte-Carlo (kMC) model for simulating the movement of platinum particles on supports, based on atom-by-atom diffusion on the surface the particle. The proposed model was able to reproduce equilibrium cluster shapes predicted using Wulff-construction. The diffusivity of platinum particles was simulated both purely based on random motion and assisted using a drift velocity. The overall particle diffusivity increases with temperature, however the extracted activation barrier appears to be temperature independent. In addition, this barrier was found to increase with particle size, as well as, with the adhesion between the particle and the support.
Download or read book Molecular Model for the Interaction of Charged Nano Particles with Metal Surfaces written by Liangliang Su and published by . This book was released on 2019 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Atomic clusters and nanoparticles Agregats atomiques et nanoparticules written by C. Guet and published by Springer Science & Business Media. This book was released on 2002-01-10 with total page 595 pages. Available in PDF, EPUB and Kindle. Book excerpt: Focused on basic science, this book reviews experiments on metal clusters in two long pedagogically written articles. Interested readers will also find articles ranging from density functional theory to computer simulations of cluster dynamics.
Download or read book Application of Quantum Mechanical Models in Nanotechnology written by Özlem Ünver and published by . This book was released on 2003 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Catalogus von Schilderyen written by and published by . This book was released on 1764 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quantum Mechanical Studies of Interactions in Model Catalytic Surfaces written by Sara E. Mason and published by . This book was released on 2007 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: Collectively, the works presented in this thesis bring forward a set of accomplishments highlighting the comprehension DFT modeling can provide. The insights obtained accredit these modeling methods further for future studies aimed at both improving fundamental understanding and guiding novel catalyst design.
Download or read book Quantum Dissipation and Decoherence of Collective Excitations in Metallic Nanoparticles written by Guillaume Weick and published by . This book was released on 2006 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quantum Mechanical Models of Nanomagnetism in Transition Metal Clusters and Diluted Magnetic Semiconductors written by Tor Olof Strandberg and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Structure and Atomic Configurations of Metal Alloy Surfaces and Nanoparticles written by Eric Michael Caruana and published by . This book was released on 2008 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fabrication of Surface Metal Nanoparticles and Their Induced Surface Plasmon Coupling with Subsurface Quantum Wells written by 黃哲偉 and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Plasmonic Nanoparticles in the Quantum Size Regime written by Jonathan Andrew Scholl and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanotechnology development has been majorly driven by the dramatic alteration and emergence of new material properties as dimensions are decreased. In recent years, noble metal nanoparticles have attracted substantial interest owing to their ability to manipulate light on the nanoscale through localized surface plasmon resonances (LSPRs). These collective oscillations of conduction band electrons result in strong optical absorption and scattering in subwavelength structures and enable applications including molecular detection, cancer treatment, and tunable nanoantennas. While the plasmonic properties of individual particles with diameters> 10 nm and multiparticle systems with gap sizes> 1 nm have been experimentally characterized and well-described with classical electrodynamic theory, LSPRs in smaller nanostructures have historically been poorly understood. Experimental observations below these dimensional thresholds have been limited by optical detection and fabrication techniques, precluding analysis of a size regime with the potential for ultrasensitive monitoring and catalysis. This dissertation describes newly-developed approaches to probe plasmonic nanoparticle systems as their dimensions enter the quantum size regime. Our approach relies on scanning transmission electron microscopy (STEM) and electron energy-loss spectroscopy (EELS), which allow high-resolution correlation of plasmonic nanoparticle structure with spectra. First, we explore individual metallic nanoparticles with diameters ranging from 20 nm down to 2 nm. As the particles transition from a classical to a quantum-influenced regime, they reveal substantial resonance shifts that deviate from classical electrodynamic predictions. An analytical quantum mechanical model is developed to explain this divergence as function of altered particle permittivity, accounting for the discretization of energy states as particle diameter decreases. Next, resonantly-coupled multiparticle systems including dimers and trimers are discussed. Using a novel electron beam manipulation technique, the separation distance between adjacent particles can be reduced to Angstrom scales. Experimental EELS analysis of dimers reveals non-classical spectral trends and that closely correlate with state-of-the-art quantum models incorporating electron tunneling. Trimers are additionally found to support a greater variety of resonant modes through selective electron beam excitation, and demonstrate both classical and non-classical spectral evolution at sub-nanometer gaps. The study of these quantum-influenced single and multiparticle systems will inform the design of future ultrafine plasmonic sensors, as well as support new interdisciplinary exploration bridging molecular electronics, nonlinear optics, and plasmonics.
Download or read book Design and Characterization of a Reversible Metal insulator Transition in Silver Quantum Dot Monolayers written by Charles Patrick Collier and published by . This book was released on 1998 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Models of Non adiabatic Dynamics at Metal Surfaces written by Thomas Olsen and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
