Exploring Chemical Concepts Through Theory and Computation

Deep, theoretical resource on the essence of chemistry, explaining a variety of important concepts including redox states and bond types Exploring Chemical Concepts Through Theory and Computation provides a comprehensive account of how the three widely used theoretical frameworks of valence bond theory, molecular orbital theory, and density functional theory, along with a variety of important chemical concepts, can between them describe and efficiently and reliably predict key chemical parameters and phenomena. By comparing the three main theoretical frameworks, readers will become competent in choosing the right modeling approach for their task. The authors go beyond a simple comparison of existing algorithms to show how data-driven theories can explain why chemical compounds behave the way they do, thus promoting a deeper understanding of the essence of chemistry. The text is contributed to by top theoretical and computational chemists who have turned computational chemistry into today’s data-driven and application-oriented science. Exploring Chemical Concepts Through Theory and Computation discusses topics including: Orbital-based approaches, density-based approaches, chemical bonding, partial charges, atoms in molecules, oxidation states, aromaticity and antiaromaticity, and acidity and basicity Electronegativity, hardness, softness, HSAB, sigma-hole interactions, charge transport and energy transfer, and homogeneous and heterogeneous catalysis Electrophilicity, nucleophilicity, cooperativity, frustration, homochirality, and energy decomposition Chemical concepts in solids, excited states, spectroscopy and machine learning, and catalysis and machine learning, as well as key connections between related concepts Aimed at both novice and experienced computational, theoretical, and physical chemists, Exploring Chemical Concepts Through Theory and Computation is an essential reference to gain a deeper, more advanced holistic understanding of the field of chemistry as a whole.

Table of Contents:
Preface xv Foreword xvii 10 Questions About Exploring Chemical Concepts Through Theory and Computation xix 1 Chemical Concepts from Molecular Orbital Theory 1 Feng Long Gu, Jincheng Yu, and Weitao Yang 1.1 Introduction 1 1.2 Molecular Orbital Theory 2 1.3 Canonical Molecular Orbitals 5 1.4 Frontier Molecular Orbital Theory 5 1.5 Localized Molecular Orbitals 6 1.6 Regularized Nonorthogonal Localized Molecular Orbitals 11 1.7 Molecular Orbitalets 15 2 Chemical Concepts from Ab Initio Valence Bond Theory 23 Chen Zhou, Fuming Ying, and Wei Wu 2.1 Introduction 23 2.2 Ab Initio Valence Bond Theory 24 2.3 Chemical Concepts in VB Theory 31 2.4 A Brief Guide to Perform VB Calculations 36 2.5 Concluding Remarks 38 3 Chemical Concepts from Conceptual Density Functional Theory 43 Frank De Proft 3.1 Introduction 43 3.2 The Fundamentals: Density Functional Theory (DFT) and Kohn-Sham DFT 46 3.3 The First Derivatives: The Electronic Chemical Potential and the Electron Density 48 3.4 The Second Derivatives: Chemical Hardness, Fukui Function, Linear Response Function, and Related Quantities 51 3.5 Perturbational Perspective of Chemical Reactivity 62 3.6 Conclusions 64 4 Chemical Concepts from Density-Based Approaches in Density Functional Theory 71 Dongbo Zhao, Xin He, Chunying Rong, and Shubin Liu 4.1 Introduction 71 4.2 Four Density-Based Frameworks 72 4.3 Applications of Density-Based Approaches 79 4.4 Concluding Remarks 94 5 Chemical Bonding 101 Sudip Pan and Gernot Frenking 5.1 Introduction 101 5.2 The Physical Mechanism of the Chemical Bond 103 5.3 Bonding Models 108 5.4 Bond Length and Bond Strength 111 5.5 Dative and Electron-Sharing Bonds 120 5.6 Polar Bonds 124 5.7 Atomic Partial Charges and Atomic Electronegativity 130 5.8 Chemical Bonding in Main-Group Compounds: N2, CO, BF, LiF 131 5.9 Chemical Bonding of the Heavier Main-Group Atoms 135 5.10 Chemical Bonding in Transition Metal Complexes: M(CO)n (M = Ni, Fe, Cr, Ti, Ca; n = 4 - 8) 143 5.11 Summary 146 6 Partial Charges 161 Tian Lu and Qinxue Chen 6.1 Concept of Partial Charge 161 6.2 Methods of Calculating Partial Charges 166 6.3 Partial Charges of Typical Molecules 176 6.4 Computer Codes for Evaluating Partial Charges 179 6.5 Concluding Remarks 180 7 Atoms in Molecules 189 Ángel Martín Pendás, Evelio Francisco, Julen Munárriz, and Aurora Costales 7.1 Introduction 189 7.2 The Quantum Theory of Atoms in Molecules (QTAIM) 190 7.3 QTAIM Atoms as Open Quantum Systems 194 7.4 Interacting Quantum Atoms (IQA) 200 8 Effective Oxidation States Analysis 207 Pedro Salvador 8.1 The Concept of Oxidation State 207 8.2 Oxidation State is Not Related to the Partial Charge 208 8.3 The Molecular Orbital Picture of the Ionic Approximation 210 8.4 Spin-Resolved Effective Fragment Orbitals and Effective Oxidation States (EOS) Analysis 213 8.5 EOS Analysis from Different AIM Schemes 216 8.6 Summary 220 9 Aromaticity and Antiaromaticity 223 Yago García-Rodeja and Miquel Solà 9.1 Definition of Aromaticity 223 9.2 Physical Foundation 224 9.3 Measures of Aromaticity 226 9.4 Rules of Aromaticity 233 9.5 Metallabenzenes and Related Compounds as an Example 239 10 Acidity and Basicity 251 Ranita Pal, Himangshu Mondal, and Pratim K. Chattaraj 10.1 Introduction 251 10.2 Definitions and Theories 252 10.3 CDFT-Based Reactivity Descriptors 257 10.4 CDFT-Based Electronic Structure Principles 259 10.5 Systemics of Lewis Acid-Base Reactions: Drago-Wayland Equation 261 10.6 Strengths of Acid and Bases 262 10.7 Effect of External Perturbation 267 10.8 CDFT and Acidity 270 10.9 CDFT and ITA 272 10.10 Are Strong Brønsted Acids Necessarily Strong Lewis Acids? 276 10.11 Summary 278 11 Sigma Hole Supported Interactions: Qualitative Features, Various Incarnations, and Disputations 285 Kelling J. Donald 11.1 Introduction 285 11.2 Many Incarnations and Roles of a Single Phenomenon 288 11.3 Related Interactions Elsewhere in the Main Group 304 11.4 Contested Interpretations 308 11.5 Conclusions 308 12 On the Generalization of Marcus Theory for Two-State Photophysical Processes 317 Chao-Ping Hsu and Chou-Hsun Yang 12.1 Introduction 317 12.2 The Golden Rule Rate Expression 318 12.3 Application 325 12.4 Conclusion 330 13 Computational Modeling of CO2 Reduction and Conversion via Heterogeneous and Homogeneous Catalysis 335 Yue Zhang, Lin Zhang, Denghui Ma, Xinrui Cao, and Zexing Cao 13.1 Introduction 335 13.2 Computational Methods 336 13.3 Activation and Reduction of CO2 338 13.4 Catalytic Coupling of CO2 with CH4 345 13.5 Homogeneous Catalytic Conversion of CO2 348 13.6 Conclusion and Outlook 352 14 Excited States in Conceptual DFT 361 Frédéric Guégan, Guillaume Hoffmann, Henry Chermette, and Christophe Morell 14.1 Introduction 361 14.2 Exploring Ground State Properties Thanks to Excited States 361 14.3 Exploring the Reactivity of Excited States with Excited States 371 14.4 Conclusion 375 15 Modeling the Photophysical Processes of Organic Molecular Aggregates with Inclusion of Intermolecular Interactions and Vibronic Couplings 379 WanZhen Liang, Yu-Chen Wang, Shishi Feng, and Yi Zhao 15.1 Introduction 379 15.2 Theoretical Approaches 381 15.3 Concluding Remarks 397 16 Duality of Conjugated Π Electrons 407 Yirong Mo 16.1 Introduction 407 16.2 The New Concept of Intramolecular Multibond Strain 412 16.3 Theoretical Method 413 16.4 Computational Analysis of the Concept of Intramolecular Multibond Strain 416 16.5 Experimental Evidence 422 16.6 Summary 426 17 Energy Decomposition Analysis and Its Applications 433 Peifeng Su 17.1 Introduction 433 17.2 Methodology 437 17.3 Applications of GKS-EDA 442 17.4 Conclusion 450 18 Chemical Concepts in Solids 455 Peter C. Müller, David Schnieders, and Richard Dronskowski 18.1 The Three Schisms of Solid-State Chemistry 455 18.2 Bloch’s Theorem 457 18.3 Basis Sets 460 18.4 Interpretational Tools 462 18.5 Applications 470 18.6 Summary 477 19 Toward Interpretable Machine Learning Models for Predicting Spectroscopy, Catalysis, and Reactions 481 Jun Jiang and Shubin Liu 19.1 Introduction 481 19.2 ML in a Nutshell 481 19.3 Chemistry-Based Descriptors as ML Features 485 19.4 Selected ML Applications 493 19.5 Concluding Remarks 507 20 Learning Design Rules for Catalysts Through Computational Chemistry and Machine Learning 513 Aditya Nandy and Heather J. Kulik 20.1 Computational Catalysis 513 20.2 Machine Learning (ML) in Catalysis 529 20.3 Summary 545 References 546 Index 559

About the Author :
Dr. Shubin Liu, PhD, is a Senior Computational Scientist at the Research Computing Center and an Adjunct Professor in the Department of Chemistry, University of North Carolina at Chapel Hill. He has been an independent researcher since 2000, focusing on developing a chemical reactivity theory using density functional theory language. Dr. Liu has authored over 270 peer-reviewed publications and is recognized in the field by various scientific awards including the Wiley-IJQC Young Investigator Award. He edited the book Conceptual Density Functional Theory, published by Wiley-VCH in April 2022, and initiated and co/organized the series of international symposiums on Chemical Concepts from Theory and Computation (CCTC).