Download or read book Ab Initio Simulation of Materials Under Extreme Conditions written by and published by . This book was released on 2005 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of materials properties under extreme conditions has made considerable progress over the past decade due to both improvements in experimental techniques and advanced modeling methods. The availability of accurate models is crucial in order to analyze experimental results obtained in extreme conditions of pressure and temperature where experimental data can be scarce. Among theoretical models, ab initio simulations are playing an increasingly important role due to their ability to predict materials properties without the need for any experimental input. Ab initio simulations also allow for an exploration of materials properties in conditions that are unachievable using controlled experiments--such as e.g. the conditions prevailing in the core of large planets. In that limit, they constitute the only quantitative model of condensed matter available today. In this article, we review the current status of ab initio simulations and discuss examples of recent applications in which numerical simulations have provided an essential complement to experimental data.
Download or read book Materials Under Extreme Conditions written by A. K. Tyagi and published by Elsevier. This book was released on 2017-01-13 with total page 872 pages. Available in PDF, EPUB and Kindle. Book excerpt: Materials Under Extreme Conditions: Recent Trends and Future Prospects analyzes the chemical transformation and decomposition of materials exposed to extreme conditions, such as high temperature, high pressure, hostile chemical environments, high radiation fields, high vacuum, high magnetic and electric fields, wear and abrasion related to chemical bonding, special crystallographic features, and microstructures. The materials covered in this work encompass oxides, non-oxides, alloys and intermetallics, glasses, and carbon-based materials. The book is written for researchers in academia and industry, and technologists in chemical engineering, materials chemistry, chemistry, and condensed matter physics. Describes and analyzes the chemical transformation and decomposition of a wide range of materials exposed to extreme conditions Brings together information currently scattered across the Internet or incoherently dispersed amongst journals and proceedings Presents chapters on phenomena, materials synthesis, and processing, characterization and properties, and applications Written by established researchers in the field
Download or read book Materials Under Extreme Conditions Molecular Crystals At High Pressure written by Vincenzo Schettino and published by World Scientific. This book was released on 2013-11-20 with total page 373 pages. Available in PDF, EPUB and Kindle. Book excerpt: High-pressure materials research has been revolutionized in the past few years due to technological breakthroughs in the diamond anvil cell (DAC), shock wave compression and molecular dynamic simulation (MD) methods. The application of high pressure, especially together with high temperature, has revealed exciting modifications of physical and chemical properties even in the simplest molecular materials.Besides the fundamental importance of these studies to understand the composition and the dynamics of heart and planets' interior, new materials possessing peculiar characteristics of hardness and composition have been synthesized at very high pressure, while unexpected chemical reactions of simple molecules to polymers and amorphous compounds have been found at milder conditions.The variety of the phenomena observed in these extreme conditions and of the materials involved provides a common ground bridging scientific communities with different cultural and experimental backgrounds. This monograph will provide a timely opportunity to report on recent progress in the field.
Download or read book Computational Approaches for Chemistry Under Extreme Conditions written by Nir Goldman and published by Springer. This book was released on 2019-02-18 with total page 293 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents recently developed computational approaches for the study of reactive materials under extreme physical and thermodynamic conditions. It delves into cutting edge developments in simulation methods for reactive materials, including quantum calculations spanning nanometer length scales and picosecond timescales, to reactive force fields, coarse-grained approaches, and machine learning methods spanning microns and nanoseconds and beyond. These methods are discussed in the context of a broad range of fields, including prebiotic chemistry in impacting comets, studies of planetary interiors, high pressure synthesis of new compounds, and detonations of energetic materials. The book presents a pedagogical approach for these state-of-the-art approaches, compiled into a single source for the first time. Ultimately, the volume aims to make valuable research tools accessible to experimentalists and theoreticians alike for any number of scientific efforts, spanning many different types of compounds and reactive conditions.
Download or read book Numerical Modeling of Materials under Extreme Conditions written by Yao Shen and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this reprint, the underlying damage mechanisms of materials used under extreme conditions are explored using computer simulation and modelling methods, presenting important information to predict the lifetime of related facilities. The scope of this reprint embraces numerical work on material responses to extreme conditions, such as high-speed impact or loading, neutron or ion irradiation, and high-pressure and/or high-temperature environments. Related simulation results based on the first principle method, molecular dynamics, and finite element methods are reported. Results of various topics have been reported by papers collected in this book, for example, including fitting a better empirical potential, diffusion of atoms on surface, corrosion, interaction between different defects, elastic constants calculations, effect of hot press forming on collision toughness and energy distribution, and influence of radiation defects on the thermo-mechanical properties of UO2. Furthermore, a review about the experiments and models for the effect of strain rate on NiTi shape memory alloys (SMAs) has also been included in this reprint. These new results present new knowledge for understanding the damage mechanisms of materials under extreme conditions, which would be useful not only for researchers in these fields but also for new readers to learn about basic concepts and current research progress to better understand the response of materials under extreme conditions.
Download or read book Numerical Modeling of Materials Under Extreme Conditions written by Yao Shen and published by Mdpi AG. This book was released on 2023-05-29 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book, the underlying damage mechanisms of materials used under extreme conditions are explored using computer simulation and modelling methods, presenting important information to predict the lifetime of related facilities. The scope of this book embraces numerical work on material responses to extreme conditions, such as high-speed impact or loading, neutron or ion irradiation, and high-pressure and/or high-temperature environments. Related simulation results based on the first principle method, molecular dynamics, and finite element methods are reported. Results of various topics have been reported by papers collected in this book, for example, including fitting a better empirical potential, diffusion of atoms on surface, corrosion, interaction between different defects, elastic constants calculations, effect of hot press forming on collision toughness and energy distribution, and influence of radiation defects on the thermo-mechanical properties of UO2. Furthermore, a review about the experiments and models for the effect of strain rate on NiTi shape memory alloys (SMAs) has also been included in this book. These new results present new knowledge for understanding the damage mechanisms of materials under extreme conditions, which would be useful not only for researchers in these fields but also for new readers to learn about basic concepts and current research progress to better understand the response of materials under extreme conditions.
Download or read book Studying Bonding and Electronic Structures of Materials Under Extreme Conditions written by Shibing Wang and published by Stanford University. This book was released on 2011 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent advances in high pressure diamond anvil cell techniques and synchrotron radiation characterization methods have enabled investigation of a wide range of materials properties in-situ under extreme conditions. High pressure studies have made significant contribution to our understanding in a number of scientific fields, e.g. condensed matter physics, chemistry, Earth and planetary sciences, and material sciences. Pressure, as a fundamental thermodynamic variable, can induce changes in the electronic and structural configuration of a material, which in turn can dramatically alter its properties. The novel phases and new compounds existing at high pressure have improved our basic understanding of bonding and interactions in condensed matter. This dissertation focuses on how pressure affects materials' bonding and electronic structures in two types of systems: hydrogen rich molecular compounds and strongly correlated transition metal oxides. The interaction of boranes and hydrogen was studied using optical microscopy and Raman spectroscopy and their hydrogen storage potential is discussed in the context of practical applications. The pressure-induced behavior of the SiH4 + H2 binary system and the formation of a newly formed compound SiH4(H2)2 were investigated using a combination of optical microscopy, Raman spectroscopy and x-ray diffraction. The experimental work along with DFT calculations on the electronic properties of the compound up to the possible metallization pressure, indicated that there are strong intermolecular interactions between SiH4 and H2 in the condensed phase. By using a newly developed synchrotron x-ray spectroscopy technique, we were able to follow the evolution of the 3d band of a 3d transition metal oxide, Fe2O3 under pressure, which experiences a series of structural, electronic and spin transitions at approximately 50 GPa. Together with theoretical calculations we revisited its electronic phase transition mechanism, and found that the electronic transitions are reflected in the pre-edge region.
Download or read book Ab initio Calculation Tutorial written by Ryo Maezono and published by Springer Nature. This book was released on 2023-05-16 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook covers the framework of first-principles analysis applied to materials using density functional theory (DFT). It provides a set of hands-on tutorials using the Quantum ESPRESSO package, an open-source software for DFT. The tutorials are well chosen, designed for maximum effectiveness while requiring a minimum of the reader’s time, and the book describes how the essential components are combined to create the practical applications based on the idea of modeling practical problems of materials. The book carefully explains how to prepare the platform to run the tutorials assisted by free software. This textbook is useful for students in experimental laboratories, for industrial researchers, and for those not majoring in theoretical studies but learning individually.
Download or read book Reactor Fuels Materials and Systems under Extreme Environments written by Wenzhong Zhou and published by Frontiers Media SA. This book was released on 2022-03-25 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Computational Materials Science written by Kaoru Ohno and published by Springer. This book was released on 2018-04-14 with total page 433 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook introduces modern techniques based on computer simulation to study materials science. It starts from first principles calculations enabling to calculate the physical and chemical properties by solving a many-body Schroedinger equation with Coulomb forces. For the exchange-correlation term, the local density approximation is usually applied. After the introduction of the first principles treatment, tight-binding and classical potential methods are briefly introduced to indicate how one can increase the number of atoms in the system. In the second half of the book, Monte Carlo simulation is discussed in detail. Problems and solutions are provided to facilitate understanding. Readers will gain sufficient knowledge to begin theoretical studies in modern materials research. This second edition includes a lot of recent theoretical techniques in materials research. With the computers power now available, it is possible to use these numerical techniques to study various physical and chemical properties of complex materials from first principles. The new edition also covers empirical methods, such as tight-binding and molecular dynamics.
Download or read book Ab Initio Molecular Dynamics written by Dominik Marx and published by Cambridge University Press. This book was released on 2009-04-30 with total page 503 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ab initio molecular dynamics revolutionized the field of realistic computer simulation of complex molecular systems and processes, including chemical reactions, by unifying molecular dynamics and electronic structure theory. This book provides the first coherent presentation of this rapidly growing field, covering a vast range of methods and their applications, from basic theory to advanced methods. This fascinating text for graduate students and researchers contains systematic derivations of various ab initio molecular dynamics techniques to enable readers to understand and assess the merits and drawbacks of commonly used methods. It also discusses the special features of the widely used Car–Parrinello approach, correcting various misconceptions currently found in research literature. The book contains pseudo-code and program layout for typical plane wave electronic structure codes, allowing newcomers to the field to understand commonly used program packages and enabling developers to improve and add new features in their code.
Download or read book Study of Performance and Characteristics of Materials Under Extreme Environment Using the ReaxFF Reactive Molecular Dynamics Simulations written by Ali Rahnamoun and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary focus of this work is the study of different materials at extreme environment. These extreme environments include Atomic Oxygen (AO) impacts, ice cluster impacts, noble gas ions irradiation and electron irradiation on different materials. AO is the most abundant element in the low Earth orbit (LEO). It is the result of the dissociation of molecular oxygen by ultraviolet radiation from the sun. In the LEO, AO collides with the materials used on spacecraft surfaces and causes degradation of these materials. The degradation of the materials on the surface of spacecraft at LEO has been a significant problem for a long time. Kapton polyimide, polyhedral oligomeric silsesquioxane (POSS), silica, and Teflon are the materials used in spacecraft industry. Degradation caused by AO impact is an important issue in these materials applications on spacecraft surface. To investigate the surface chemistry of these materials in exposure to space AO, a computational chemical evaluation of the Kapton polyimide, POSS, amorphous silica, and Teflon was performed in separate simulations under similar conditions. For performing these simulations, the ReaxFF reactive force-field program was used, which provides the computational tool required to perform molecular dynamics (MD) simulations on system sizes sufficiently large to describe the full chemistry of the reactions. Using these simulations, the effects of AO impact on different materials and the role of impact energies, the content of material, and the temperature of material on their behavior are studied. The ReaxFF results indicate that Kapton is less resistant than Teflon against AO damage. These results are in good agreement with the MISSE experimental results. In the MISSE projects, the mass loss of different materials is studied during space missions. These simulations indicate that the amorphous silica shows the highest stability among these materials before the start of the highly exothermic silicon oxidation. We have verified that adding silicon to the bulk of the Kapton structure enhances the stability of the Kapton against AO impact. Our canonical MD simulations demonstrate that an increase in the heat transfer in materials during AO impact can provide a considerable decrease in the disintegration of the material. This effect is especially relevant in silica AO collision. During aircraft or spacecraft missions, ice accumulates on different parts of their surface. We studied the dynamics of the collisions between amorphous silica structures and amorphous and crystal ice clusters with impact velocities of 1, 4 and 7 km/s using the ReaxFF reactive molecular dynamics simulation method. The 1km/s and lower impact velocities can happen during aircraft missions and the impact velocities higher than 1 km/s can happen during spacecraft missions. The initial ice clusters consist of 150 water molecules for the amorphous ice cluster and 128 water molecules for the crystal ice cluster. The ice clusters are collided on the surface of amorphous fully oxidized and suboxide silica. These simulations show that at 1 km/s impact velocities, all the ice clusters accumulate on the surface and at 4 km/s and 7 km/s impact velocities, some of the ice cluster molecules bounce back from the surface. We also studied the effect of the second ice cluster impacts on the surfaces which are fully covered with ice, in particular their mass loss/accumulation. These studies show that at 1 km/s impacts, the entire ice cluster accumulates on the silica surface. At 7 km/s impact velocity some ice molecules, which are part of the ice layers accreted on the silica surface, will separate from the ice layers on the surface. At 4 km/s ice cluster impact, ice accumulation is observed for the crystal ice cluster impacts and ice separation is observed for the amorphous ice impacts. Observing the temperatures of the ice clusters during the collisions indicates that the possibility of electron excitation at impact velocities less than 10 km/s is minimal and ReaxFF reactive molecular dynamics simulation can predict the chemistry of these hypervelocity impacts.However, at impact velocities close to 10 km/s the average temperature of the impacting ice clusters increase to about 2000K, with individual molecules occasionally reaching temperatures of over 8000K and thus it will be prudent to consider the concept of electron excitation at these higher impact velocities, which goes beyond the current ReaxFF ability. An important parameter affecting the ability to remove this ice from the surface is the heat transfer characteristics of the accumulated ice. The ice heat transfer is related to the process of ice formation and its density and internal structure. We investigated the effects of ice and silica structure and the ice cluster attachment mechanism to the silica surface on the thermal conductivity (TC) of the attached ice cluster using the ReaxFF reactive molecular dynamics method. The purpose of this study is to investigate the thermal transport in amorphous and crystalline ice after deposition on the silica surfaces. A dual thermostat method was applied for the calculation of TC values. The validity of this method was verified by comparing the calculated values of TC for crystal and amorphous ice with available experimental values. Our calculations show that the TC value for both crystal and amorphous ice drop after deposition on the silica surfaces. This decrease in the TC is more significant for the ice deposition on suboxide silica surfaces. Furthermore, crystal ice shows higher TC values than amorphous ice after accumulation. However, when crystal ice impacts on the silica surface at 1 km/s impact speed, the crystalline shape of the ice cluster is lost to a considerable level and the TC values obtained for the ice clusters in such cases are closer to amorphous ice TC values. We observed a decrease in the TC values when ionic species are added inside the ice clusters. We studied Kr noble gas ions irradiations on graphene, and the subsequent annealing of the irradiated graphene. Different types of defects were generated in graphene after noble gas ion irradiations. Kr irradiation mostly caused mono vacancy defects in graphene while light noble v gas ions can mostly generate Stone-Wales defects in graphene. The irradiated graphene was annealed between 300K and 2000K and the reconstruction of the defects was studied. In order to study the electron beam irradiation on Kapton using molecular simulation, electron beams irradiation at random positions of Kapton are modeled. For changing the amount of energy transfer to Kapton, each electron beam is irradiated for 1fs or 2fs. The temperature evolution and chemical composition changes in Kapton during and after electron beam irradiation was studied. The changes in chemical composition of Kapton are compared to the experimental results. This study shows that the time of each electron beam irradiation has considerable effect on the amount of energy transferred to Kapton. Kapton decomposition takes place at different Kapton temperatures under different electron irradiation conditions. At the start of decomposition, small molecules separate from the surface and with continuing electron irradiation, larger molecules start to separate from the surface. As our simulations demonstrate, ReaxFF can provide a cost-effective screening tool for future material optimization for applications in extreme environments.
Download or read book Mineral Behaviour at Extreme Conditions written by Ronald Miletich and published by The Mineralogical Society of Great Britain and Ireland. This book was released on 2005-01-01 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Intrinsic Structures and Properties of Energetic Materials written by Chaoyang Zhang and published by Springer Nature. This book was released on 2023-06-30 with total page 469 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book highlights the intrinsic structures of all kinds of energetic compounds and some structure–property relationships therein. Energetic materials are a class of energy materials that can transiently release a large amount of gases and heat by self-redox after stimulated and usually refer to explosives, propellants and pyrotechnics. Nowadays, in combination with various theories and simulation-aided material design technologies, many new kinds of energetic materials like energetic extended solids, energetic ionic salts, energetic metal organic frames, energetic co-crystals and energetic perovskites have been created, in addition to traditional energetic molecular crystals. It is somewhat dazzling, and an issue of how we can understand these new types of energetic materials is raised. In the past about 20 years, we were immersed in the computational energetic materials. By means of defining a concept of intrinsic structures of energetic materials, which refers to the crystal packing structure of energetic materials, as well as molecule for molecular solid specially, the microscopic structures have been mostly clarified, and related with many macroscopic properties and performances, with molecular simulations. This book presents our understanding about it. Thereby, a simply and new way to readily understand energetic materials is expected to be paved, based on this book. It contains energetic molecular crystals, energetic ionic crystals, energetic atomic crystals, energetic metallic crystals and energetic mixed-type crystals and the substructures closest to crystal packing. Meanwhile, the common intermolecular interactions in energetic crystals will be introduced. In addition, theoretical and simulation methods for treating the intrinsic structures will be briefed, as they are the main tools to reveal the molecules and crystals. Besides, the polymorphism as a level of intrinsic structures will be briefly discussed. In the final of this book, we introduce the crystal engineering of energetic materials. This book features the first proposal of intrinsic structure and crystal engineering of energetic materials and the understanding of the properties and performances of energetic materials by maintaining a concept that structure determines property. It helps to promote the rationality in creating new energetic materials, rather than increase experience.
Download or read book Multiscale Materials Modelling written by Z. X. Guo and published by Elsevier. This book was released on 2007-05-31 with total page 307 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multiscale materials modelling offers an integrated approach to modelling material behaviour across a range of scales from the electronic, atomic and microstructural up to the component level. As a result, it provides valuable new insights into complex structures and their properties, opening the way to develop new, multi-functional materials together with improved process and product designs. Multiscale materials modelling summarises some of the key techniques and their applications. The various chapters cover the spectrum of scales in modelling methodologies, including electronic structure calculations, mesoscale and continuum modelling. The book covers such themes as dislocation behaviour and plasticity as well as the modelling of structural materials such as metals, polymers and ceramics. With its distinguished editor and international team of contributors, Multiscale materials modelling is a valuable reference for both the modelling community and those in industry wanting to know more about how multiscale materials modelling can help optimise product and process design. Reviews the principles and applications of mult-scale materials modelling Covers themes such as dislocation behaviour and plasticity and the modelling of structural materials Examines the spectrum of scales in modelling methodologies, including electronic structure calculations, mesoscale and continuum modelling
Download or read book Energetic Materials written by John R. Sabin and published by Academic Press. This book was released on 2014-02-10 with total page 357 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Quantum Chemistry presents surveys of current topics in this rapidly developing field that has emerged at the cross section of the historically established areas of mathematics, physics, chemistry, and biology. It features detailed reviews written by leading international researchers. This volume focuses on the theory of heavy ion physics in medicine. This volume presents a series of articles concerning current important topics in quantum chemistry. The invited articles are written by the best people in the field
Download or read book Molecular Modeling of the Sensitivities of Energetic Materials written by Didier Mathieu and published by Elsevier. This book was released on 2022-04-01 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: Molecular Modeling of the Sensitivities of Energetic Materials, Volume 22 introduces experimental aspects, explores the relationships between sensitivity, molecular structure and crystal structure, discusses insights from numerical simulations, and highlights applications of these approaches to the design of new materials. Providing practical guidelines for implementing predictive models and their application to the search for new compounds, this book is an authoritative guide to an exciting field of research that warrants a computer-aided approach for the investigation and design of safe and powerful explosives or propellants. Much recent effort has been put into modeling sensitivities, with most work focusing on impact sensitivity and leading to a lot of experimental data in this area. Models must therefore be developed to allow evaluation of significant properties from the structure of constitutive molecules. Highlights a range of approaches for computational simulation and the importance of combining them to accurately understand or estimate different parameters Provides an overview of experimental findings and knowledge in a quick and accessible format Presents guidelines to implement sensitivity models using open-source python-related software, thus supporting easy implementation of flexible models and allowing fast assessment of hypotheses
