A unique overview of the different kinds of chemical bonds that can be found in the periodic table, from the main-group elements to transition elements, lanthanides and actinides. It takes into account the many developments that have taken place in the field over the past few decades due to the rapid advances in quantum chemical models and faster computers. This is the perfect complement to "Chemical Bonding - Fundamentals and Models" by the same editors, who are two of the top scientists working on this topic, each with extensive experience and important connections within the community.

Gernot Frenking studied chemistry at the Technical University Aachen (Germany). He then became a research atudent in the group of Prof. Kenichi Fukui in Kyoto (Japan) and completed his PhD and his habilitation at Technical University Berlin (Germany). He was then a visiting scientist at the University of California, Berkeley (USA) and a staff scientist at SRI International in Menlo Park, California (USA). Since 1990 he is Professor for Computational Chemistry at the Philipps-Universitat Marburg. Sason Shaik is a graduate of the University of Washington (USA), where he also obtained his PhD. After a postdoctoral year at Cornell University, he became Lecturer at Ben-Gurion University of the Negev (Israel), where he became Professor in 1988. In 1992 he moved to The Hebrew University where he is Professor and the Director of the Lise Meitner-Minerva Center for Computational Quantum Chemistry.

Preface CHEMICAL BONDING OF MAIN-GROUP ELEMENTS Introduction and Definitions The Lack of Radial Nodes of the 2p Shell Accounts for Most of the Peculiarities of the Chemistry of the 2p-Elements The Role of the Outer d-Orbitals in Bonding Secondary Periodicities: Incomplete-Screening and Relativistic Effects "Honorary d-Elements": the Peculiarities of Structure and Bonding of the Heavy Group 2 Elements Concluding Remarks MULTIPLE BONDING OF HEAVY MAIN-GROUP ATOMS Introduction Bonding Analysis of Diatomic Molecules E2 (E = N - Bi) Comparative Bonding Analysis of N2 and P2 with N4 and P4 Bonding Analysis of the Tetrylynes HEEH (E = C - Pb) Explaining the Different Structures of the Tetrylynes HEEH (E = C - Pb) Energy Decomposition Analysis of the Tetrylynes HEEH (E = C - Pb) Conclusion THE ROLE OF RECOUPLED PAIR BONDING IN HYPERVALENT MOLECULES Introduction Multireference Wavefunction Treatment of Bonding Low-Lying States of SF and OF Low-Lying States of SF2 and OF2 (and Beyond) Comparison to Other Models Concluding Remarks DONOR-ACCEPTOR COMPLEXES OF MAIN-GROUP ELEMENTS Introduction Single-Center Complexes EL2 Two-Center Complexes E2L2 Summary and Conclusion ELECTRON-COUNTING RULES IN CLUSTER BONDING - POLYHEDRAL BORANES, ELEMENTAL BORON, AND BORON-RICH SOLIDS Introduction Wade's Rule Localized Bonding Schemes for Bonding in Polyhedral Boranes 4n + 2 Interstitial Electron Rule and Ring-Cap Orbital Overlap Compatibility Capping Principle Electronic Requirement of Condensed Polyhedral Boranes - mno Rule Factors Affecting the Stability of Condensed Polyhedral Clusters Hypoelectronic Metallaboranes Electronic Structure of Elemental Boron and Boron-Rich Metal Borides - Application of Electron-Counting Rules Conclusion BOUND TRIPLET PAIRS IN THE HIGHEST SPIN STATES OF MONOVALENT METAL CLUSTERS Introduction Can Triplet Pairs Be Bonded? Origins of NPFM Bonding in n+1Lin Clusters Generalization of NPFM Bonding in n+1Lin Clusters NPFM Bonding in Coinage Metal Clusters Valence Bond Modeling of the Bonding in NPFM Clusters of the Coinage Metals NPFM Bonding: Resonating Bound Triplet Pairs Concluding Remarks: Bound Triplet Pairs Appendix CHEMICAL BONDING IN TRANSITION METAL COMPOUNDS Introduction Valence Orbitals and Hybridization in Electron-Sharing Bonds of Transition Metals Carbonyl Complexes TM(CO)6q (TMq = Hf2-, Ta-, W, Re+, Os2+, Ir3+) Phosphane Complexes (CO)5TM-PR3 and N-Heterocyclic Carbene Complexes (CO)5TM-NHC (TM = Cr, Mo, W) Ethylene and Acetylene Complexes (CO)5TM-C2Hn and Cl4TM-C2Hn (TM = Cr, Mo, W) Group-13 Diyl Complexes (CO)4Fe-ER ( E = B - Tl; R = Ph, Cp) Ferrocene Fe(n5-Cp)2 and Bis(benzene)chromium Cr(n6-Bz)2 Cluster, Complex, or Electron-Sharing Compound? Chemical Bonding in Mo(Eh)12 and Pd(EH)8 (E = Zn, Cd, Hg) Metal-Metal Multiple Bonding Summary CHEMICAL BONDING IN OPEN-SHELL TRANSITION-METAL COMPLEXES Introduction Theoretical Foundations Qualitative Interpretation Spin Density Distributions - A Case Study Summary MODELING METAL-METAL MULTIPLE BONDS WITH MULTIREFERENCE QUANTUM CHEMICAL METHODS Introduction Multireferance Methods and Effective Bond Orders The Multiple Bond in Re2Cl8 2- Homonuclear Diatomic Molecules: Cr2, Mo2, and W2 Cr2, Mo2, and W2 Containing Complexes Fe2 Complexes Concluding Remarks THE QUANTUM CHEMISTRY OF TRANSITION METAL SURFACE BONDING AND REACTIVITY Introduction The Elementary Quantum-Chemical Model of the Surface Chemical Bond Quantum Chemistry of the Surface Chemical Bond Metal Particle Composition and Size Dependence Lateral Interactions; Reconstruction Adsorbate Bond Activation and Formation Transition State Analysis: A Summary CHEMICAL BONDING OF LANTHANIDES AND ACTINIDES Introduction Technical Issues The Energy Decomposition Approach to the Bonding in f Block Compounds f Block Applications of the Electron Localization Function Does Covalency Increase or Decrease across the Actinide Series? Multi-configurational Descriptions of Bonding in f Element Complexes Concluding Remarks DIRECT ESTIMATE OF CONJUGATION, HYPERCONJUGATION, AND AROMATICITY WITH THE ENERGY DECOMPOSITION ANALYSIS METHOD Introduction The EDA Method Conjugation Hyperconjugation Aromaticity Concluding Remarks MAGNETIC PROPERTIES OF AROMATIC COMPOUNDS AND AROMATIC TRANSITION STATES Introduction A Short Historical Review of Aromaticity Magnetic Properties of Molecules Examples Concluding Remarks CHEMICAL BONDING IN INORGANIC AROMATIC COMPOUNDS Introduction How to Recognize Aromaticity and Antiaromaticity? "Conventional" Aromatic/Antiaromatic Inorganic Molecules "Unconventional" Aromatic/Antiaromatic Inorganic Molecules Summary and Perspectives CHEMICAL BONDING IN SOLIDS Introduction Electronic Structure of Solids: Basic Notions Bonding in Solids: Some Illustrative Cases Concluding Remarks DISPERSION INTERACTION AND CHEMICAL BONDING Introduction A Short Survey of the Theory of the London Dispersion Energy Theoretical Methods to Compute the Dispersion Energy Selected Examples Conclusion Computational Details HYDROGEN BONDING Introduction Fundamental Properties of Hydrogen Bonds Hydrogen Bonds with Varying Strengths Hydrogen Bonds in Biological Molecules Theoretical Description of Hydrogen Bonding Summary DIRECTIONAL ELECTROSTATIC BONDING Introduction Anisotropic Molecular Electrostatic Potential Distribution Around Atoms Electrostatic Anisotropy, Donor-Acceptor Interactions and Polarization Purely Electrostatic Models Difference-Density Techniques Directional Noncovalent Interactions Conclusions Index