Kinetic Monte Carlo simulations of crystal surfaces
Author: Stefan Schinzer
Publisher:
Published: 2000
Total Pages: 132
ISBN-13: 9783826572388
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Monte Carlo Simulation of Adsorption Processes on Heterogeneous Crystal Surfaces
Author: Leila Rajabibonab
Publisher:
Published: 2017
Total Pages: 150
ISBN-13:
DOWNLOAD EBOOKThe simulation of adsorption processes on a heterogeneous crystal surface is the main interest of this thesis. Two applications of this event have been developed with Kinetic Monte Carlo simulation. One is how to control the crystal growth by macromolecules and the other is how to measure the effective rate of interactions near a crystal surface. The first part of this thesis, considers the effective rate of catalytic conversion on a heterogeneous catalytic surface. We assume the crystal surface has two types of active site, one is neutral and the other one is highly active. We compared our result from simulation with the analytical method that is given by the homogenization theory. Our result revealed the importance of patterns of surface energies and the size of them on reaction rate. In the second project we consider the adsorption of a homopolymer chain on a crystal surface with two types of surface energies in order to limit the growth of one site and let the other sites grow more. We developed a new Kinetic Monte Carlo simulation method in this part, which was also applied to block copolymer chains that are more complex than a homo-polymer chain. Using this method four important phases of the polymer chains at high temperatures and also the free energies of the system across different patterns of active sites have been found. We tested different types of co-polymers to find the most differentiative block copolymer for controlling the crystal growth.
An Introduction to Kinetic Monte Carlo Simulations of Surface Reactions
Author: A.P.J. Jansen
Publisher: Springer
Published: 2012-05-31
Total Pages: 266
ISBN-13: 364229488X
DOWNLOAD EBOOKKinetic Monte Carlo (kMC) simulations still represent a quite new area of research, with a rapidly growing number of publications. Broadly speaking, kMC can be applied to any system describable as a set of minima of a potential-energy surface, the evolution of which will then be regarded as hops from one minimum to a neighboring one. The hops in kMC are modeled as stochastic processes and the algorithms use random numbers to determine at which times the hops occur and to which neighboring minimum they go. Sometimes this approach is also called dynamic MC or Stochastic Simulation Algorithm, in particular when it is applied to solving macroscopic rate equations. This book has two objectives. First, it is a primer on the kMC method (predominantly using the lattice-gas model) and thus much of the book will also be useful for applications other than to surface reactions. Second, it is intended to teach the reader what can be learned from kMC simulations of surface reaction kinetics. With these goals in mind, the present text is conceived as a self-contained introduction for students and non-specialist researchers alike who are interested in entering the field and learning about the topic from scratch.
A Study of Surface Growth Mechanism by Kinetic Monte-Carlo Simulation
Author: Min Gong
Publisher: Open Dissertation Press
Published: 2017-01-27
Total Pages:
ISBN-13: 9781374666733
DOWNLOAD EBOOKThis dissertation, "A Study of Surface Growth Mechanism by Kinetic Monte-Carlo Simulation" by Min, Gong, 鞏旻, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled A STUDY OF SURFACE GROWTH MECHANISM BY KINETIC MONTE-CARLO SIMULATION submitted by Gong Min for the degree of Master of Philosophy at The University of Hong Kong in December 2006 Semiconductor represents one of the most important materials that have contributed to the advancement of technology and growth of world's economy in the past few decades. As one of the major techniques to grow semiconductor materials and the associated device structures, Molecular-Beam Epitaxy (MBE) has been intensively used in both research and production. To fully utilize the great potentials of the MBE technique, it is important to understand the microscopic growth processes and thus to improve the quality of the grown films. In this thesis study, kinetic Monte-Carlo (KMC) simulation is employed to study the relationship between microscopic surface processes and macroscopic morphology of grown surfaces. Specifically, the traditional solid-on-solid (SOS) deposition-diffusion model is applied on both hcp(0001) flat and 1-dimensional (1D) vicinal surfaces to investigate the effects of binding energy anisotropy and the energy barrier at specific steps. Pertinent to surfactant mediated growth, a model involving the site-exchange process during growth has also been considered on hcp(0001) flat and vicinal surfaces as well as on fcc(001) flat surface. Furthermore, to compare different growth models and mechanisms, the number density and size distribution of nucleation islands are examined as a function of temperature. It is found that triangular island shape and double-step bunching can be caused by anisotropy of either binding energy of atoms at steps or the energy barriers for site-exchange at steps. On the other hand, multiple step bunching may be attributed to positive energy barriers for adatom incorporation at ascending steps. A "negative" Ehrlich-Schwoebel barrier at surface descending steps will have little effect on the morphology of a surface. It is also found that the diffusion-limited growth gives rise to an increasing linear relation between the logarithm of island number density and the reciprocal of temperature, while in the site-exchange dominated growth, a decreasing linear relation is observed between the logarithm of island density and the reciprocal of substrate temperature. The 'critical island size' for nucleation can vary from 0 to at least 2 as temperature changes in the diffusion-limited growth, while for the site-exchange growth, the 'critical island size' is 0 as reflected by the monotonic decay of island density with the size. DOI: 10.5353/th_b3763619 Subjects: Molecular-beam epitaxy Monte Carlo method Crystal growth
A Kinetic Monte Carlo Simulation of Submonolayer Crystal Growth
Author: Pushpa Raj Pudasaini
Publisher: LAP Lambert Academic Publishing
Published: 2011-08-01
Total Pages: 100
ISBN-13: 9783845417271
DOWNLOAD EBOOKThe physics of surface and interface is an increasingly important area in the field of condensed matter physics. This book provides a comprehensive introduction to the kinetic Monte Carlo simulation for the submonolayer crystal growth phenomenon. The growth from vapor is studied under the condition meet in molecular beam epitaxy (MBE). It describes the basic physical processes, such as atomic process during growth, formulation of growth models, and surface diffusion and nucleation theory. It covers the effect of small-cluster mobility and adatom detachment on the island formation during the submonolayer epitaxial growth of the thin films deposition under the various conditions. This book may be useful for the undergraduates, graduate students and researchers in the field of surface and interface physics.
Monte Carlo Simulations of Temperature-programmed and Isothermal Desorption from Single-crystal Surfaces
Author: Stephen John Lombardo
Publisher:
Published: 1990
Total Pages: 642
ISBN-13:
DOWNLOAD EBOOKKinetic Monte Carlo Models for Crystal Defects
Author: Kyle Louis Golenbiewski
Publisher:
Published: 2016
Total Pages: 71
ISBN-13:
DOWNLOAD EBOOKKinetic Monte Carlo algorithms have become an increasingly popular means to simulate stochastic processes since their inception in the 1960's. One area of particular interest is their use in simulations of crystal growth and evolution in which atoms are deposited on, or hop between, predefined lattice locations with rates depending on a crystal's conguration. Two such applications are heteroepitaxial thin films and grain boundary migration. Heteroepitaxial growth involves depositing one material onto another with a different lattice spacing. This misfit leads to long-range elastic stresses that affect the behavior of the film. Grain boundary migration, on the other hand, describes how the interface between oriented crystals evolves under a driving force. In ideal grain growth, migration is driven by curvature of the grain boundaries in which the boundaries move towards their center of curvature. This results in a reduction of the total grain boundary surface area of the system, and therefore the total energy of the system. We consider both applications here. Specically, we extend the analysis of an Energy Localization Approximation applied to Kinetic Monte Carlo simulations of two-dimensional film growth to a three-dimensional setting. We also propose a Kinetic Monte Carlo model for grain boundary migration in the case of arbitrarily oriented face-centered cubic crystals.
Dynamics of Crystal Surfaces and Interfaces
Author: P.M. Duxbury
Publisher: Springer Science & Business Media
Published: 2006-04-11
Total Pages: 248
ISBN-13: 0306470713
DOWNLOAD EBOOKThis series of books, which is published at the rate of about one per year, addresses fundamental problems in materials science. The contents cover a broad range of topics from small clusters of atoms to engineering materials and involve chemistry, physics, and engineering, with length scales ranging from Ångstroms up to millimeters. The emphasis is on basic science rather than on applications. Each book focuses on a single area of current interest and brings together leading experts to give an up-to-date discussion of their work and the work of others. Each article contains enough references that the interested reader can access the relevant literature. Thanks are given to the Center for Fundamental Materials Research at Michigan State University for supporting this series. M. F. Thorpe, Series Editor E-mail: thorpe@pa. msu. edu v PREFACE th th During the period 4 -8 August 1996, a conference with the same title as this book was held in Traverse City, Michigan. That conference was organized as a sequel to an interesting and successful WEM workshop in a similar area run by Profs. Hans Bonzel and Bill Mullins in May 1995. This book contains papers presented at the Traverse City conference. The book focuses on: atomic processes, step structure and dynamics; and their effect on surface and interface structures and on the relaxation kinetics of larger leng- scale nonequilibrium morphologies.
Monte Carlo Simulations of Temperature-programmed and Isothermal Desorption from Single-crystal Surfaces
Author:
Publisher:
Published: 1990
Total Pages: 316
ISBN-13:
DOWNLOAD EBOOKThe kinetics of temperature-programmed and isothermal desorption have been simulated with a Monte Carlo model. Included in the model are the elementary steps of adsorption, surface diffusion, and desorption. Interactions between adsorbates and the metal as well as interactions between the adsorbates are taken into account with the Bond-Order-Conservation-Morse-Potential method. The shape, number, and location of the TPD peaks predicted by the simulations is shown to be sensitive to the binding energy, coverage, and coordination of the adsorbates. In addition, the occurrence of lateral interactions between adsorbates is seen to strongly effect the distribution of adsorbates is seen to strongly effect the distribution of adsorbates on the surface. Temperature-programmed desorption spectra of a single type of adsorbate have been simulated for the following adsorbate-metal systems: CO on Pd(100); H2 on Mo(100); and H2 on Ni(111). The model predictions are in good agreement with experimental observation. TPD spectra have also been simulated for two species coadsorbed on a surface; the model predictions are in qualitative agreement with the experimental results for H2 coadsorbed with strongly bound atomic species on Mo(100) and Fe(100) surfaces as well as for CO and H2 coadsorbed on Ni(100) and Rh(100) surfaces. Finally, the desorption kinetics of CO from Pd(100) and Ni(100) in the presence of gas-phase CO have been examined. The effect of pressure is seen to lead to an increase in the rate of desorption relative to the rate observed in the absence of gas-phase CO. This increase arises as a consequence of higher coverages and therefore stronger lateral interactions between the adsorbed CO molecules.
Monte Carlo Methods in Finance
Author: Peter Jäckel
Publisher: John Wiley & Sons
Published: 2002-04-03
Total Pages: 245
ISBN-13: 047149741X
DOWNLOAD EBOOKAn invaluable resource for quantitative analysts who need to run models that assist in option pricing and risk management. This concise, practical hands on guide to Monte Carlo simulation introduces standard and advanced methods to the increasing complexity of derivatives portfolios. Ranging from pricing more complex derivatives, such as American and Asian options, to measuring Value at Risk, or modelling complex market dynamics, simulation is the only method general enough to capture the complexity and Monte Carlo simulation is the best pricing and risk management method available. The book is packed with numerous examples using real world data and is supplied with a CD to aid in the use of the examples.
