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Preface to the Third Editionxvii Extract from the Preface to the Second Editionxix Extracts from the Preface to the First Editionxxiii Foreword to the First Editionxxv Mathematical Symbolsxxvii Abbreviationsxxxiii 1 Introduction: Subject and Methods 1
1.1 Objectives 1
1.1.1 Molecular Engineering and Intuitive Guesswork 1
1.1.2 Main Objectives of This Book in Comparison with Other Sources 4
1.2 Definitions of Chemical Bonding and Transition Metal Coordination System 8
1.2.1 Chemical Bonding as an Electronic Phenomenon 8
1.2.2 Definition of Coordination System 10
1.3 The Schrödinger Equation 13
1.3.1 Formulation 13
1.3.2 Role of Approximations 15 Summary Notes 16 References 17 2 Atomic States 19
2.1 One-Electron States 19
2.1.1 Angular and Radial Functions 19
2.1.2 Orbital Overlaps: Hybridized Functions 25
2.1.3 Spin-Orbital Interaction 29
2.1.4 Relativistic Atomic Functions 31
2.2 Multielectron States: Energy Terms 38
2.2.1 Electronic Configurations and Terms 38
2.2.2 Multielectron Wavefunctions 43
2.2.3 Slater-Condon and Racah Parameters 45
2.2.4 The Hartree-Fock Method 50 Summary Notes 54 Questions 55 Exercises and Problems 55 References 56 3 Symmetry Ideas and Group-Theoretical Description 59
3.1 Symmetry Transformations and Matrices 60
3.2 Groups of Symmetry Transformations 66
3.3 Classification of Point Groups 67
3.4 Representations of Groups and Matrices of Representations 71
3.5 Classification of Molecular Terms and Vibrations, Selection Rules, and The Wigner-Eckart Theorem 78
3.6 Construction of Symmetrized Molecular Orbitals and Normal Vibrations 83
3.7 The Notion of Double Groups 92 Summary Notes 93 Exercises and Problems 94 References 95 4 Crystal Field Theory 97
4.1 Introduction 97
4.1.1 Brief History 97
4.1.2 Main Assumptions 98
4.2 Splitting of the Energy Levels of One d Electron in Ligand Fields 99
4.2.1 Qualitative Aspects and Visual Interpretation 99
4.2.2 Calculation of the Splitting Magnitude 105
4.2.3 Group-Theoretical Analysis 111
4.3 Several d Electrons 114
4.3.1 Case of a Weak Field 114
4.3.2 Strong Crystal Fields and Low- and High-Spin Complexes 120
4.3.3 Energy Terms of Strong-Field Configurations 125
4.3.4 Arbitrary Ligand Fields and Tanabe-Sugano Diagrams 127
4.4 f-Electron Term Splitting 134
4.5 Crystal Field Parameters and Extrastabilization Energy 137
4.6 Limits of Applicability of Crystal Field Theory 141 Summary Notes 143 Questions 144 Exercises and Problems 145 References 146 5 Molecular Orbitals and Related Description of Electronic Structure 149
5.1 Basic Ideas of the MO LCAO Method 149
5.1.1 Main Assumptions 149
5.1.2 Secular Equation 151
5.1.3 Classification by Symmetry 152
5.1.4 Symmetrized Orbitals 156
5.1.5 Simplification of the Secular Equation 158
5.1.6 A Short Note on Band Structure of Transition Metal Solids 160
5.2 Charge Distribution and Bonding in the MO LCAO Method. The Case of Weak Covalency 161
5.2.1 Atomic Charges and Bond Orders 161
5.2.2 Bonding, Nonbonding, and Antibonding Orbitals 165
5.2.3 Case of Weak Covalency 168
5.2.4 Angular Overlap Model 170
5.3 Methods of Calculation of MO Energies and LCAO Coefficients 173
5.3.1 SCF MO LCAO Approximation 173
5.3.2 Electron Correlation Effects 176
5.3.3 Basis Sets and Pseudopotentials 182
5.4 Density Functional Theory 192
5.4.1 Hohenberg-Kohn (HK) Method 192
5.4.2 Exchange-Correlation Functional 196
5.4.3 Time-Dependent DFT (TD-DFT) 201
5.4.4 Density-Functional Tight Binding (DFTB) 202
5.5 Electronic Structure Calculations for Large Polyatomic Systems 209
5.5.1 Fragmentary Calculations 209
5.5.2 Molecular Mechanics 213
5.5.3 Combined Quantum/Classical (QM/MM) Methods 218
5.5.4 Machine Learning Force Fields (MLFF) Method 231
5.6 Comparison of Methods and Computer Programs 232 Summary Notes 239 Exercises and Problems 240 References 241 6 Electronic Structure and Chemical Bonding 249
6.1 Classification of Chemical Bonds by Electronic Structure and Role of d and f Electrons in Coordination Bonding 249
6.1.1 Criticism of the Genealogical Classification 249
6.1.2 Classification by Electronic Structure and Properties 252
6.1.3 Features of Coordination Bonds 254
6.1.4 Coordination Bonding by Pre- and Post-transition Elements 256
6.2 Qualitative Aspects and Electronic Configurations 258
6.2.1 Most Probable MO Schemes 258
6.2.2 Electronic Configurations in Low- and High-Spin Complexes 260
6.2.3 Covalence Electrons and Ionization Potentials 263
6.3 Ligand Bonding 267
6.3.1 General Considerations: Multiorbital Bonds 267
6.3.2 Mono-orbital Bonds: Coordination of NH 3 and H 2 O 272
6.3.3 Diorbital Bonds: Coordination of the N 2 Molecule 274
6.3.4 Coordination of Carbon Monoxide 277
6.3.5 Ï? + Ï? Bonding 282
6.3.6 CO Bonding on Surfaces 285
6.3.7 Bonding of NO 288
6.3.8 Coordination of C 2 H 4 289
6.3.9 Metal-Metal Bonds and Bridging Ligands 295
6.4 Energies, Geometries, and Charge Distributions 303
6.4.1 Ionization Energies 303
6.4.2 Total and Bonding Energies, Geometries, and Other Properties 307
6.5 Relativistic Effects 315
6.5.1 Relativistic Approaches 316
6.5.2 Orbital Contraction and Valence Activity 319
6.5.3 Bond Lengths, Bond Energies, and Vibrational Frequencies 322
6.5.4 Correlation Between Spin-Orbital Splitting and Bonding 327
6.5.5 Other Relativistic Effects 331 Summary Notes 332 Exercises and Problems 333 References 335 7 Vibronic Coupling in Formation, Deformation, and Transformation of Polyatomic Systems. The Jahn-Teller Effects 343
7.1 Molecular Vibrations 344
7.1.1 Adiabatic Approximation 344
7.1.2 Normal Coordinates and Harmonic Vibrations 347
7.1.3 Special Features of Vibrations of Coordination Compounds 354
7.2 Vibronic Coupling 356
7.2.1 Vibronic Constants 356
7.2.2 Orbital Vibronic Constants 358
7.3 The Jahn-Teller Effects 363
7.3.1 The Jahn-Teller Theorem 363
7.3.2 The Pseudo-Jahn-Teller Effect 368
7.3.3 Hidden-Jahn-Teller and Hidden Pseudo-Jahn-Teller Effects. Four Modifications of Jahn-Teller Effects 369
7.3.4 Configurations with h-PJTE and Spin Crossover 374
7.3.5 The Renner-Teller Effect 378
7.3.6 The Jahn-Teller Effect in a Twofold-Degenerate Electronic State 379
7.3.7 Threefold-Degenerate Electronic States 391
7.4 Pseudo-Jahn-Teller Effect and the Two-Level Paradigm 396
7.4.1 Pseudo-Jahn-Teller (PJT) Instability 396
7.4.2 Uniqueness of the Vibronic Mechanism of Structural Configuration Instability. The Two-Level Paradigm 404
7.4.3 Further Insight into the Pseudo-JTE and Hidden JTE 409 Summary Notes 415 Exercises and Problems 416 References 417 8 Electronic Structure Investigated by Physical Methods 421
8.1 Band Shapes of Electronic Spectra 422
8.1.1 Qualitative Interpretation of Vibrational Broadening 422
8.1.2 Theory of Absorption Band Shapes 425
8.1.3 Band Shapes of Electronic Transitions Between Nondegenerate States; Zero-Phonon Lines 428
8.1.4 Types of Electronic Transitions on Intensity 432
8.2 d-d, Charge Transfer, Infrared, and Raman Spectra 436
8.2.1 Origin and Special Features of d-d Transitions 436
8.2.2 Spectrochemical and Nephelauxetic Series 441
8.2.3 Charge Transfer Spectra 445
8.2.4 Infrared Absorption and Raman Scattering 449
8.2.5 Transitions Involving Orbitally Degenerate States 454
8.3 X-ray and Ultraviolet Photoelectron Spectra; EXAFS 457
8.3.1 General Ideas 457
8.3.2 Electron Relaxation; Shakeup and CI Satellites 462
8.3.3 Chemical Shift 467
8.3.4 EXAFS and Related Methods 471
8.4 Magnetic Properrties 474
8.4.1 Magnetic Moment and Quenching of Orbital Contribution 474
8.4.2 Paramagnetic Susceptibility 479
8.4.3 Electron Spin Resonance (ESR) 481
8.4.4 Magnetic Exchange Coupling 489
8.4.5 Spin Crossover 497
8.4.6 Magnetic Circular Dichroism (MCD) 500
8.5 Gamma-resonance Spectroscopy 503
8.5.1 The Mossbauer Effect 503
8.5.2 γ-Resonance Spectra 505
8.5.3 Isomer Shift and Quadrupole Splitting in GRS 505
8.5.4 Hyperfine Splitting 510
8.6 Electron Charge and Spin Density distribution in Diffraction Method 514
8.6.1 The Method of Deformation Density 514
8.6.2 Spin Densities from Neutron Scattering 524 Summary Notes 526 Exercises and Problems 528 References 532 9 Stereochemistry and Crystal Chemistry 539
9.1 Definitions. Semiclassical Approaches 539
9.1.1 The Notion of Molecular Shape 539
9.1.2 Directed Valences, Localized Electron Pairs, and Valence Shell Electron Pair Repulsion (VSEPR) 543
9.1.3 Nonbonding Orbitals and Nodal Properties 547
9.1.4 Complementary Spherical Electron Density Model 550
9.2 Vibronic Effects in Stereochemistry 555
9.2.1 Nuclear Motion Effects: Relativity to the Means of Observation and Vibronic Amplification of Distortions 555
9.2.2 Qualitative Stereochemica