Quantum Information Theory Of Molecular States

The Quantum Information Theory (IT) perspective on entropic origins of the molecular electronic structure and chemical reactivity is examined in this book. The classical IT of Fisher and Shannon has already provided sensitive probes of the chemical bond patterns in molecules, generating tools for the bond spatial localization, formulating entropic measures of its overall multiplicity, and providing indices of the bond covalent/ionic composition. However, the amount of information carried by the particle distribution alone is not sufficient for a complete IT description of complex wavefunctions in molecular quantum mechanics, e.g., degenerate electronic states. The latter exhibit finite spatial phases and generate nonvanishing electronic currents. This monograph emphasizes the entropic chemical concepts due to the phase part of electronic states.

The field of atomic, molecular, and optical (AMO) science underpins many technologies and continues to progress at an exciting pace for both scientific discoveries and technological innovations. AMO physics studies the fundamental building blocks of functioning matter to help advance the understanding of the universe. It is a foundational discipline within the physical sciences, relating to atoms and their constituents, to molecules, and to light at the quantum level. AMO physics combines fundamental research with practical application, coupling fundamental scientific discovery to rapidly evolving technological advances, innovation and commercialization. Due to the wide-reaching intellectual, societal, and economical impact of AMO, it is important to review recent advances and future opportunities in AMO physics. Manipulating Quantum Systems: An Assessment of Atomic, Molecular, and Optical Physics in the United States assesses opportunities in AMO science and technology over the coming decade. Key topics in this report include tools made of light; emerging phenomena from few- to many-body systems; the foundations of quantum information science and technologies; quantum dynamics in the time and frequency domains; precision and the nature of the universe, and the broader impact of AMO science.

Chemical Reactivity in Quantum Mechanics and Information Theory introduces a thermodynamic-like description of molecular systems and provides an objective treatment of their fragments. The book formulates adequate entropic tools for probing in chemical terms and the electronic structure of molecules and rationalizing reactivity principles. It covers the information origins of chemical bonds, covalent/ionic composition, trends in molecular stability and reactivity, equilibrium polarizations and charge-transfer reconstructions of reactive complexes, as well as the phase/current promotions of molecular substrates. In addition, the book introduces a precise descriptor of molecular fragments and clarifies mostly intuitive semantics of several chemical concepts. Readers will find a precise and unbiased description of chemical reactivity phenomena in Donor-Acceptor systems in terms of quantum states and generalized concepts of Information/Communication theories. Generates a new basis for understanding the rules governing molecular processes, information origins of chemical bonding, and its covalent/ionic composition Provides an objective approach to classical issues in modern reactivity theory Offers a unifying information-theoretic perspective on electronic states

Over recent decades, the increase in computational resources, coupled with the popularity of competitive quantum mechanics alternatives (particularly DFT), has promoted the widespread penetration of quantum mechanics calculations into a variety of fields targeting the reactivity of molecules. This book presents a selection of original research papers and review articles illustrating diverse applications of quantum mechanics in the study of problems involving molecules and their reactivity.

Polish Quantum Chemistry from Kolos to Now, Volume 87 provides a survey of contributions coauthored by Polish scientists working in Poland, and in European and American Universities. Sections in this release include Review: From the Kolos-Wolniewicz calculations to the quantum-electrodynamic treatment of the hydrogen molecule: competition between theory and experiment, Review: How to make symmetry-adapted perturbation theory more accurate, Review: Advanced models of coupled cluster theory for the ground, excited and ionized states, Can orbital basis sets compete with explicitly correlated ones for few-electron systems?, Converging high-level equation-of-motion coupled-cluster energetics with the help of Monte Carlo and selected configuration interaction, and more. Additional chapters cover Coupled cluster downfolding techniques: a review of existing applications in classical and quantum computing for chemical systems, Exploring the attosecond laser-driven electron dynamics in the hydrogen molecule with different real-time time-dependent configuration interaction approaches, Molecular systems in spatial confinement: variation of linear and nonlinear electrical response of molecules in the bond dissociation processes, and much more. Updates on the latest developments and performance of SAPT Presents key theory and applications of high precision calculations for few electron systems Includes discussions on the development and applications of the DFT approach

This new volume, Research Methodologies and Practical Applications of Chemistry, presents a detailed analysis of current experimental and theoretical approaches surrounding chemical science. With an emphasis on multidisciplinary as well as interdisciplinary applications, the book extensively reviews fundamental principles and presents recent research to help show logical connections between the theory and application of modern chemistry concepts. It also emphasizes the behavior of materials from the molecular point of view. The burgeoning field of chemistry and chemical science has led to many recent technological innovations and discoveries. Understanding the impact of these technologies on business, science, and industry is an important first step in developing applications for a variety of settings and contexts. The aim of this book is to present research that has transformed this discipline and aided its advancement. The book examines the strengths and future potential of chemical technologies in a variety of industries.

The growth of technology for chemical assessment has led to great developments in the investigation of chemical reactivity in recent years, but key information is often dispersed across many different research fields. Exploring both traditional and advanced methods, Chemical Reactivity, Volume 2: Approaches and Applications present the latest approaches and strategies for the computational assessment of chemical reactivity.Following an insightful introduction, the book begins with an overview of conformer searching techniques before progressing to explore numerous different techniques and methods, including confined environments, quantum similarity descriptors, volume-based thermodynamics and polarizability. A unified approach to the rules of aromaticity is followed by methods for assessing interaction energies and the role of electron density for varied different analyses. Algorithms for confirmer searching, partitioning and a whole range of quantum chemical methods are also discussed.Consolidating the knowledge of a global team of experts in the field, Chemical Reactivity, Volume 2: Approaches and Applications is a useful resource for both students and researchers interested in applying and refining their use of the latest approaches for assessing chemical reactivity in their own work. Compiles a broad range of contemporary methods and approaches for reactivity and structure prediction Highlights the application of chemical reactivity strategies for the investigation of such areas as aromaticity, halogen bonds, and electronic materials Includes discussion of computational tools for exploring molecular spaces from different angles, including interaction energies, quantum similarity, and electron density

Mathematics Applied to Engineering in Action: Advanced Theories, Methods, and Models focuses on material relevant to solving the kinds of mathematical problems regularly confronted by engineers. This new volume explains how an engineer should properly define the physical and mathematical problem statements, choose the computational approach, and solve the problem by a proven reliable approach. It presents the theoretical background necessary for solving problems, including definitions, rules, formulas, and theorems on the particular theme. The book aims to apply advanced mathematics using real-world problems to illustrate mathematical ideas. This approach emphasizes the relevance of mathematics to engineering problems, helps to motivate the reader, and gives examples of mathematical concepts in a context familiar to the research students. The volume is intended for professors and instructors, scientific researchers, students, and industry professionals. It will help readers to choose the most appropriate mathematical modeling method to solve engineering problems.