This book presents the state-of-the-art in simulation on supercomputers. Leading researchers present results achieved on systems of the High Performance Computing Center Stuttgart (HLRS) for the year 2012. The reports cover all fields of computational science and engineering ranging from CFD via computational physics and chemistry to computer science with a special emphasis on industrially relevant applications. Presenting results for both vector-systems and micro-processor based systems the book allows to compare performance levels and usability of various architectures. As HLRS operates not only a large cluster system but also one of the largest NEC vector systems in the world this book gives an excellent insight also into the potential of vector systems. The book covers the main methods in high performance computing. Its outstanding results in achieving highest performance for production codes are of particular interest for both the scientist and the engineer. The book comes with a wealth of coloured illustrations and tables of results.

The authors of this volume illustrate recent trends in the design and application of accurate force fields. 15 papers reflect the present questions including the strategies for (i) the inclusion of the polarization energy and (ii) an optimal parametrization of models. They highlight the directions to follow as new exciting fields of application emerge. Expert authors discuss the optimization and parametrization of new models, put in perspectives the actual importance of the polarization energy, as well as review or propose new models explicitly for incorporating polarization. They also present models that are applied to difficult systems or challenging fields of application. Originally published in the journal Theoretical Chemistry Accounts, these outstanding contributions are now available in a hardcover print format. This volume is of benefit in particular to those research groups and libraries that have chosen to have only electronic access to the journal. It also provides valuable content for all researchers in theoretical chemistry.

This concise book introduces and discusses the basic theory of conical intersections with applications in atomic, molecular and condensed matter physics. Conical intersections are linked to the energy of quantum systems. They can occur in any physical system characterized by both slow and fast degrees of freedom - such as e.g. the fast electrons and slow nuclei of a vibrating and rotating molecule - and are important when studying the evolution of quantum systems controlled by classical parameters. Furthermore, they play a relevant role for understanding the topological properties of condensed matter systems. Conical intersections are associated with many interesting features, such as a breakdown of the Born-Oppenheimer approximation and the appearance of nontrivial artificial gauge structures, similar to the Aharonov-Bohm effect. Some applications presented in this book include - Molecular Systems: some molecules in nonlinear nuclear configurations undergo Jahn-Teller distortions under which the molecule lower their symmetry if the electronic states belong to a degenerate irreducible representation of the molecular point group. - Solid State Physics: different types of Berry phases associated with conical intersections can be used to detect topologically nontrivial states of matter, such as topological insulators, Weyl semi-metals, as well as Majorana fermions in superconductors. - Cold Atoms: the motion of cold atoms in slowly varying inhomogeneous laser fields is governed by artificial gauge fields that arise when averaging over the fast internal degrees of freedom of the atoms. These gauge fields can be Abelian or non-Abelian, which opens up the possibility to create analogs to various relativistic effects at low speed.

Designing molecules and materials with desired properties is an important prerequisite for advancing technology in our modern societies. This requires both the ability to calculate accurate microscopic properties, such as energies, forces and electrostatic multipoles of specific configurations, as well as efficient sampling of potential energy surfaces to obtain corresponding macroscopic properties. Tools that can provide this are accurate first-principles calculations rooted in quantum mechanics, and statistical mechanics, respectively. Unfortunately, they come at a high computational cost that prohibits calculations for large systems and long time-scales, thus presenting a severe bottleneck both for searching the vast chemical compound space and the stupendously many dynamical configurations that a molecule can assume. To overcome this challenge, recently there have been increased efforts to accelerate quantum simulations with machine learning (ML). This emerging interdisciplinary community encompasses chemists, material scientists, physicists, mathematicians and computer scientists, joining forces to contribute to the exciting hot topic of progressing machine learning and AI for molecules and materials. The book that has emerged from a series of workshops provides a snapshot of this rapidly developing field. It contains tutorial material explaining the relevant foundations needed in chemistry, physics as well as machine learning to give an easy starting point for interested readers. In addition, a number of research papers defining the current state-of-the-art are included. The book has five parts (Fundamentals, Incorporating Prior Knowledge, Deep Learning of Atomistic Representations, Atomistic Simulations and Discovery and Design), each prefaced by editorial commentary that puts the respective parts into a broader scientific context.

London dispersion interactions are responsible for numerous phenomena in physics, chemistry and biology. Recent years have seen the development of new, physically well-founded models, and dispersion-corrected density functional theory (DFT) is now a hot topic of research. This book is an overview of current understanding of the physical origin and modelling of London dispersion forces manifested at an atomic level. It covers a wide range of system, from small intermolecular complexes, to organic molecules and crystalline solids, through to biological macromolecules and nanostructures. In presenting a broad overview of the of the physical foundations of dispersion forces, the book provides theoretical, physical and synthetic chemists, as well as solid-state physicists, with a systematic understanding of the origins and consequences of these ubiquitous interactions. The presentation is designed to be accessible to anyone with intermediate undergraduate mathematics, physics and chemistry.

This book sheds new light on the dynamical behaviour of electron spins in molecules containing two unpaired electrons (i.e. a radical pair). The quantum dynamics of these spins are made complicated by the interaction between the electrons and the many nuclear spins of the molecule; they are intractable using analytical techniques, and a naive numerical diagonalization is not remotely possible using current computational resources. Hence, this book presents a new method for obtaining the exact quantum-mechanical dynamics of radical pairs with a modest number of nuclear spins. Readers will learn how a calculation that would take 13 years using conventional wavepacket propagation can now be done in 1 day, and will also discover a new semiclassical method for approximating the dynamics in the presence of many nuclear spins. The new methods covered in this book are shown to provide significant insights into three topical and diverse areas: charge recombination in molecular wires (which can be used in artificially mimicking photosynthesis), magnetoelectroluminescence in organic light-emitting diodes, and avian magnetoreception (how birds sense the Earth's magnetic field in order to navigate).

This book reviews various aspects of molecular spectroscopy and its application in materials science, chemistry, physics, medicine, the arts and the earth sciences. Written by an international group of recognized experts, it examines how complementary applications of diverse spectroscopic methods can be used to study the structure and properties of different materials. The chapters cover the whole spectrum of topics related to theoretical and computational methods, as well as the practical application of spectroscopic techniques to study the structure and dynamics of molecular systems, solid-state crystalline and amorphous materials, surfaces and interfaces, and biological systems. As such, the book offers an invaluable resource for all researchers and postgraduate students interested in the latest developments in the theory, experimentation, measurement and application of various advanced spectroscopic methods for the study of materials.

This brief introduces readers to an alternative thermochemical reference system that makes it possible to use the heats of formation of organic compounds to deduce the energies that depend entirely on their structures, and which provides calculated values for most of the characteristic structures appearing in organic molecules. These structure-dependent energies are provided e.g. for selected compounds of normal and cyclic alkanes, open chain and cyclic olefins (including conjugated polyenes), alkynes, aromatic hydrocarbons and their substituted derivatives. The oxygen, sulfur and nitrogen derivatives of the above-mentioned compounds are also represented with calculated structure-dependent energies including alcohols, ethers, aldehydes and ketones, carboxylic acids, thiols, sulfides, amines, amides, heterocyclic compounds and others. Most organic reactions can be interpreted as the disappearance of certain structures and formation of others. If the structure-dependent energies are known, it can be shown how the disappearing and the newly formed structures contribute to the heat of reactions and to the driving forces. As experienced by the author, who pioneered the concept, structure dependent energies can help teachers to make organic chemistry more accessible for their students. Accordingly, the brief offers a valuable resource for all those who teach organic chemistry at universities, and for those who are learning it.

This book introduces basic concepts of mathematical physics to chemists. Many textbooks and monographs of mathematical physics may appear daunting to them. Unlike other, related books, however, this one contains a practical selection of material, particularly for graduate and undergraduate students majoring in chemistry. The book first describes quantum mechanics and electromagnetism, with the relation between the two being emphasized. Although quantum mechanics covers a broad field in modern physics, the author focuses on a hydrogen(like) atom and a harmonic oscillator with regard to the operator method. This approach helps chemists understand the basic concepts of quantum mechanics aided by their intuitive understanding without abstract argument, as chemists tend to think of natural phenomena and other factors intuitively rather than only logically. The study of light propagation, reflection, and transmission in dielectric media is of fundamental importance. This book explains these processes on the basis of Maxwell equations. The latter half of the volume deals with mathematical physics in terms of vectors and their transformation in a vector space. Finally, as an example of chemical applications, quantum chemical treatment of methane is introduced, including a basic but essential explanation of Green functions and group theory. Methodology developed by the author will also prove to be useful to physicists.

On-surface synthesis is appearing as an extremely promising strategy to create organic nanoarchitectures with atomic precision. Molecular building blocks holding adequate functional groups are dosed onto surfaces that support or even drive their covalent linkage. The surface confinement and the frequent lack of solvents (most commonly being performed under vacuum conditions) create a completely new scenario fully complementary to conventional chemistry. In a pedagogical way and based on the most recent developments, this volume presents our current understanding in the field, addressing fundamental reaction mechanisms, synthetic strategies to influence the reactions according to our needs, as well as the ultimate growth and characterization of functional materials. Verging on chemistry, physics and materials science, the book is aimed at students and researchers interested in nanochemistry, surface science, supramolecular materials and molecular devices. Chapters "Mechanistic insights into surface-supported chemical reactions", "Reactivity on and of Graphene Layers: Scanning Probe Microscopy Reviels" and "Bottom-up fabrication of atomically precise graphene nanoribbons" of this book are available open access under a CC BY 4.0 license at link.springer.com

This book describes the latest developments in the new research discipline of X-ray nanochemistry, which uses nanomaterials to enhance the effectiveness of X-ray irradiation. Nanomaterials now can be synthesized in such a way as to meet the demand for complex functions that enhance the X-ray effect. Innovative methods of delivering the X-rays, which can interact with those nanomaterials much more strongly than energetic electrons and gamma rays, also create new opportunities to enhance the X-ray effect. As a result, new concepts are conceived and new developments are made in the last decade, which are discussed and summarized in this book. This book will help define the discipline and encourage more students and scientists to work in this discipline. These efforts will eventually lead to formation of a full set of physical, chemical and materials principles for this new research field.

This book presents a collection of invited research and review contributions on recent advances in (mainly) theoretical condensed matter physics, theoretical chemistry, and theoretical physics. The volume celebrates the 90th birthday of N.H. March (Emeritus Professor, Oxford University, UK), a prominent figure in all of these fields. Given the broad range of interests in the research activity of Professor March, who collaborated with a number of eminent scientists in physics and chemistry, the volume embraces quite diverse topics in physics and chemistry, at various dimensions and energy scales. One thread connecting all these topics is correlation in aggregated states of matter, ranging from nuclear physics to molecules, clusters, disordered condensed phases such as the liquid state, and solid state physics, and the various phase transitions, both structural and electronic, occurring therein. A final chapter leaps to an even larger scale of matter aggregation, namely the universe and gravitation. A further no less important common thread is methodological, with the application of theoretical physics and chemistry, particularly density functional theory and statistical field theory, to both nuclear and condensed matter.

This book describes fundamental theory and recent advances of sum frequency generation (SFG) spectroscopy. SFG spectroscopy is widely used as a powerful tool of surface characterization, although theoretical interpretation of the obtained spectra has been a major bottleneck for most users. Recent advances in SFG theory have brought about a breakthrough in the analysis methods beyond conventional empirical ones, and molecular dynamics (MD) simulation of SFG spectroscopy allows for simultaneous understanding of observed spectra and interface structure in unprecedented detail. This book explains these recently understood theoretical aspects of SFG spectroscopy by the major developer of the theory. The theoretical topics are treated at basic levels for undergraduate students and are described in relation to computational chemistry, such as molecular modeling and MD simulation, toward close collaboration of SFG spectroscopy and computational chemistry in the near future.

This thesis focuses on the nanomanufacturing of graphene-a newly discovered, two-dimensional material with extraordinary properties-in order to realize its numerous potential applications. Combining experimental implementation with theoretical modelling, it investigates three classes of graphene nanostructure fabrication using particle beam irradiation: (i) doping of graphene using low energy nitrogen irradiation; (ii) joining of graphene sheets with laser and C, N, and Ar ion beam irradiation; and (iii) fabrication of graphene nanopores by means of focused ion beam and electron beam irradiation. The feasibility of the nanomanufacture of graphene using particle beam irradiation is demonstrated by various experimental methods, and the mechanisms involved under different types of beam irradiation are revealed using theoretical calculations. Further, the book analyzes the mechanical and electrical properties of the fabricated graphene nanostructures by means of atomic simulations to predict the application potentials of the proposed methods. The findings help promote the implementation of graphene-structure applications in industry.

This book is intended as an introductory lecture in material physics, in which the modern computational group theory and the electronic structure calculation are in collaboration. The first part explains how to use computer algebra for applications in solid-state simulation, based on the GAP computer algebra package. Computer algebra enables us to easily obtain various group theoretical properties, such as the representations, character tables, and subgroups. Furthermore it offers a new perspective on material design, which could be executed in a mathematically rigorous and systematic way. The second part then analyzes the relation between the structural symmetry and the electronic structure in C60 (as an example of a system without periodicity). The principal object of the study was to illustrate the hierarchical change in the quantum-physical properties of the molecule, which correlates to the reduction in the symmetry (as it descends down in the ladder of subgroups). The book also presents the computation of the vibrational modes of the C60 by means of the computer algebra. In order to serve the common interests of researchers, the details of the computations (the required initial data and the small programs developed for the purpose) are explained in as much detail as possible.

This textbook extends from the basics of femtosecond physics all the way to some of the latest developments in the field. In this updated edition, the chapter on laser-driven atoms is augmented by the discussion of two-electron atoms interacting with strong and short laser pulses, as well as by a review of ATI rings and low energy structures in photo-electron spectra. In the chapter on laser-driven molecules a discussion of 2D infrared spectroscopy is incorporated. Theoretical investigations of atoms and molecules interacting with pulsed lasers up to atomic field strengths on the order of 10^16 W/cm(2) are leading to an understanding of many challenging experimental discoveries. The presentation starts with a brief introduction to pulsed laser physics. The basis for the non-perturbative treatment of laser-matter interaction in the book is the time-dependent Schroedinger equation. Its analytical as well as numerical solution are laid out in some detail. The light field is treated classically and different possible gauges for the field-matter interaction are discussed. Physical phenomena, ranging from paradigmatic Rabi-oscillations in two-level systems to the ionization of atoms, the generation of high-order harmonics, the ionization and dissociation of molecules, as well as the control of chemical reactions are presented and discussed on a fundamental level. In this way, the theoretical background for state of the art experiments with strong and short laser pulses is given. The new text is augmented by several additional exercises and now contains a total of forty-eight problems, whose worked-out solutions are given in the last chapter. In addition, some detailed calculations are performed in the appendices. Furthermore, each chapter ends with references to more specialized literature.

This thesis presents detailed mechanistic studies on a series of important C-H activation reactions using combined computational methods and mass spectrometry experiments. It also provides guidance on the design and improvement of catalysts and ligands. The reactions investigated include: (i) a nitrile-containing template-assisted meta-selective C-H activation, (ii) Pd/mono-N-protected amino acid (MPAA) catalyzed meta-selective C-H activation, (iii) Pd/MPAA catalyzed asymmetric C-H activation reactions, and (iv) Cu-catalyzed sp3 C-H cross-dehydrogenative-coupling reaction. The book reports on a novel dimeric Pd-M (M = Pd or Ag) model for reaction (i), which successfully explains the meta-selectivity observed experimentally. For reaction (ii), with a combined DFT/MS method, the author successfully reveals the roles of MPAA ligands and a new C-H activation mechanism, which accounts for the improved reactivity and high meta-selectivity and opens new avenues for ligand design. She subsequently applies ion-mobility mass spectrometry to capture and separate the [Pd(MPAA)(substrate)] complex at different stages for the first time, providing support for the internal-base model for reaction (iii). Employing DFT studies, she then establishes a chirality relay model that can be widely applied to MPAA-assisted asymmetric C-H activation reactions. Lastly, for reaction (iv) the author conducts detailed computational studies on several plausible pathways for Cu/O2 and Cu/TBHP systems and finds a reliable method for calculating the single electron transfer (SET) process on the basis of benchmark studies.

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.

This book introduces readers to MesoBioNano (MBN) Explorer - a multi-purpose software package designed to model molecular systems at various levels of size and complexity. In addition, it presents a specially designed multi-task toolkit and interface - the MBN Studio - which enables the set-up of input files, controls the simulations, and supports the subsequent visualization and analysis of the results obtained. The book subsequently provides a systematic description of the capabilities of this universal and powerful software package within the framework of computational molecular science, and guides readers through its applications in numerous areas of research in bio- and chemical physics and material science - ranging from the nano- to the mesoscale. MBN Explorer is particularly suited to computing the system's energy, to optimizing molecular structure, and to exploring the various facets of molecular and random walk dynamics. The package allows the use of a broad variety of interatomic potentials and can, e.g., be configured to select any subset of a molecular system as rigid fragments, whenever a significant reduction in the number of dynamical degrees of freedom is required for computational practicalities. MBN Studio enables users to easily construct initial geometries for the molecular, liquid, crystalline, gaseous and hybrid systems that serve as input for the subsequent simulations of their physical and chemical properties using MBN Explorer. Despite its universality, the computational efficiency of MBN Explorer is comparable to that of other, more specialized software packages, making it a viable multi-purpose alternative for the computational modeling of complex molecular systems. A number of detailed case studies presented in the second part of this book demonstrate MBN Explorer's usefulness and efficiency in the fields of atomic clusters and nanoparticles, biomolecular systems, nanostructured materials, composite materials and hybrid systems, crystals, liquids and gases, as well as in providing modeling support for novel and emerging technologies. Last but not least, with the release of the 3rd edition of MBN Explorer in spring 2017, a free trial version will be available from the MBN Research Center website (mbnresearch.com).

This book addresses a wide range of topics relating to the properties and behavior of condensed matter under extreme conditions such as intense magnetic and electric fields, high pressures, heat and cold, and mechanical stresses. It is divided into four sections devoted to condensed matter theory, molecular chemistry, theoretical physics, and the philosophy and history of science. The main themes include electronic correlations in material systems under extreme pressure and temperature conditions, surface physics, the transport properties of low-dimensional electronic systems, applications of the density functional theory in molecular systems, and graphene. The book is the outcome of a workshop held at the University of Catania, Italy, in honor of Professor Renato Pucci on the occasion of his 70th birthday. It includes selected invited contributions from collaborators and co-authors of Professor Pucci during his long and successful career, as well as from other distinguished guest authors.

This book presents recent research on Advanced Computing in Industrial Mathematics, which is one of the most prominent interdisciplinary areas and combines mathematics, computer science, scientific computations, engineering, physics, chemistry, medicine, etc. Further, the book presents the tools of Industrial Mathematics, which are based on mathematical models, and the corresponding computer codes, which are used to perform virtual experiments to obtain new data or to better understand the existing experimental results. The book gathers the peer-reviewed papers presented during the 10th Annual Meeting of the Bulgarian Section of SIAM (BGSIAM) from December 21 to 22, 2015 in Sofia, Bulgaria.

This book is a collection of problems that are intended to aid students in graduate and undergraduate courses in Classical and Quantum Physics. It is also intended to be a study aid for students that are preparing for the PhD qualifying exam. Many of the included problems are of a type that could be on a qualifying exam. Others are meant to elucidate important concepts. Unlike other compilations of problems, the detailed solutions are often accompanied by discussions that reach beyond the specific problem.The solution of the problem is only the beginning of the learning process--it is by manipulation of the solution and changing of the parameters that a great deal of insight can be gleaned. The authors refer to this technique as "massaging the problem," and it is an approach that the authors feel increases the pedagogical value of any problem.

This thesis provides a comprehensive description of methods used to compute the vibrational spectra of liquid systems by molecular dynamics simulations. The author systematically introduces theoretical basics and discusses the implications of approximating the atomic nuclei as classical particles. The strengths of the methodology are demonstrated through several different examples. Of particular interest are ionic liquids, since their properties are governed by strong and diverse intermolecular interactions in the liquid state. As a novel contribution to the field, the author presents an alternative route toward infrared and Raman intensities on the basis of a Voronoi tessellation of the electron density. This technique is superior to existing approaches regarding the computational resources needed. Moreover, this book presents an innovative approach to obtaining the magnetic moments and vibrational circular dichroism spectra of liquids, and demonstrates its excellent agreement with experimental reference data.

This thesis presents the latest developments in new catalytic C-C bond formation methods using easily accessible carboxylate salts through catalytic decarboxylation with good atom economy, and employing the sustainable element iron as the catalyst to directly activate C-H bonds with high step efficiency. In this regard, it explores a mechanistic understanding of the newly discovered decarboxylative couplings and the catalytic reactivity of the iron catalyst with the help of density functional theory calculation. The thesis is divided into two parts, the first of which focuses on the development of a series of previously unexplored, inexpensive carboxylate salts as useful building blocks for the formation of various C-C bonds to access valuable chemicals. In turn, the second part is devoted to several new C-C bond formation methodologies using the most ubiquitous transition metal, iron, as a catalyst, and using the ubiquitous C-H bond as the coupling partner.