Boron: The Fifth Element (Challenges and Advances in Computational Chemistry and Physics Book 20)

This multi-author edited volume reviews the recent developments in boron chemistry, with a particular emphasis on the contribution of computational chemistry. The contributors come from Europe, the USA and Asia. About 60% of the book concentrates on theoretical and computational themes whilst 40% is on topics of interest to experimental chemists. Specific themes covered include structure, topology, modelling and prediction, the role of boron clusters in synthetic chemistry and catalysis, as medical agents when acting as inhibitors of HIV protease and carbonic anhydrases. Foreword Preface Contents Chapter 1: Classical and Multicenter Bonding in Boron: Two Faces of Boron 1.1 Introduction 1.2 Multicenter Bonding in Boron 1.2.1 Bonding in Pure Boron Clusters 1.2.2 Bonding in Doped Boron Clusters 1.2.3 Boron Molecular Wankel Motors 1.2.4 All-Boron Fullerenes 1.2.5 Two-Dimensional Boron Sheet 1.2.6 Competition Between 2D and 3D Structures in the BnHn+2 Species 1.3 Electronic Transmutation of Boron into “Carbon” Upon Accepting an Extra Electron 1.4 Summary References Chapter 2: Molecular Structures of Free Boron Clusters 2.1 Introduction 2.2 Methodology 2.2.1 Determination of Molecular Structures 2.2.2 Determination of Electron Distributions 2.3 Structural Analyses 2.3.1 Parent Boron Hydrides 2.3.2 Closo Heteroboranes 2.3.2.1 Icosahedral Dodecaborane(12) Derivatives 2.3.2.2 Ten- and Eleven-Vertex Closo Structures 2.3.3 Nido Heteroboranes 2.3.4 Arachno Heteroboranes 2.3.5 B4 Clusters 2.3.6 Shared Icosahedra 2.4 Conclusions References Chapter 3: Computational Studies of Metallaboranes and Metallacarboranes 3.1 Introduction 3.2 Computational Methods 3.3 Summary of Some Representative Computational Studies on Metallaboranes and Metallacarboranes 3.3.1 General Comments 3.3.2 Five-Vertex Systems 3.3.3 Six-Vertex Systems 3.3.4 Seven-Vertex Systems 3.3.5 Eight-Vertex Systems 3.3.6 Nine-Vertex Systems 3.3.7 Ten-Vertex Systems 3.3.8 11-Vertex Systems 3.3.9 12-Vertex Systems: Metal Bis(dicarbollides) 3.3.10 Other 12-Vertex Systems 3.3.11 13-vertex Systems 3.3.12 14-Vertex Systems 3.3.13 15- and 16-Vertex Systems 3.3.14 Oblatocloso (Flattened) Polyhedral Metallaboranes 3.3.15 Systems with Fused Metallaborane Polyhedra References Chapter 4: Quantum Chemistry of Excited States in Polyhedral Boranes 4.1 Introduction 4.2 Photophysics and Photochemistry Processes 4.2.1 Emission: Fluorescence 4.2.2 Non-radiative Decay 4.2.3 Emission: Phosphorescence 4.3 Computational Methods for Excited States 4.4 Strange Case of Dr Jekyll (syn-B18H22) and Mr Hyde (anti-B18H22) 4.4.1 Absorption 4.4.2 Emission 4.4.3 Geometrical Changes 4.5 Excited States in the New Polyhedral Substituted Borane 4,4′-(SH)2-anti-B18H20 4.5.1 Absorption 4.5.2 Emission 4.5.3 Geometrical Changes 4.6 Conclusions References Chapter 5: Deconvoluting the Reaction Path from B10H14 Plus BH4− to B12H122−. Can Theory Make a Contribution? 5.1 Introduction 5.2 Computational Details 5.3 Results and Discussions 5.4 Conclusions References Chapter 6: Big Borane Assemblies, Macropolyhedral Species and Related Chemistry References Chapter 7: Electronic Requirements and Structural Preferences for Large Polyhedral Boranes 7.1 Introduction 7.2 Sharing of Edges Between Polyhedra 7.3 Sharing of Single Vertex Between Polyhedra 7.4 Exo-linking of Polyhedra 7.5 Bonding in Supraicosahedral Systems 7.6 Mechanisms for Charge Compensation 7.7 Conclusion References Chapter 8: Applications of Nanocatalysis in Boron Chemistry 8.1 Introduction 8.2 Suzuki Miyaura Cross-coupling Reactions 8.3 Oxidative Homo-Coupling Reactions 8.4 Carbonylative Cross-Coupling 8.5 Hydroboration Reactions and Dehydrogenation of Boron Compounds 8.6 Isotope Exchange Reactions 8.7 Conclusions and Future Perspectives References Chapter 9: Noncovalent Interactions of Heteroboranes 9.1 Introduction 9.2 Physical Basis of Noncovalent Interactions 9.2.1 Electrostatics 9.2.2 Dispersion 9.2.3 Induction (Polarization) 9.2.4 Charge-Transfer 9.3 A Plethora of Noncovalent Interactions 9.3.1 Classical Hydrogen Bonds 9.3.2 Weak Hydrogen Bonds 9.3.3 Dihydrogen Bonds 9.3.4 σ-Hole Bonding 9.4 Methods of Study 9.4.1 Coupled Cluster Theory 9.4.2 Symmetry-Adapted Perturbation Theory (SAPT) 9.4.3 Density Functional Theory Augmented with Empirical Dispersion (DFT-D) 9.4.4 Quantum Theory of Atoms in Molecules (QTAIM) 9.4.5 Partial Atomic Charges 9.5 Conclusions and Outlook References