Quantum Chemical Methods in Main-Group Chemistry

by Klap¿tke, Thomas M.; Schulz, Axel

• ISBN13: 9780471972426
• ISBN10: 0471972428
• Edition: 1st
• Format: Hardcover
• Copyright: 1998-11-03
• Publisher: Wiley

Summary

Quantum Chemical Methods In Main-Group Chemistry Thomas M. Klap?tke Axel Schulz University of Munich, Germany With an invited chapter by Richard D. Harcourt University of Melbourne, Australia Computational quantum chemistry has emerged in recent years as a key tool for the elucidation of molecular structure and molecular properties. However, it is still sometimes regarded as a highly theoretical subject of limited practical value. In this book the authors emphasize the strong link between quantum chemical calculations and experiment. The book is a fascinating blend of theory and experiment, and deals with topical and interesting molecules, using state-of-the-art techniques and accompanied by full explanations. In Part 1 of Quantum Chemical Methods in Main-Group Chemistry, modern quantum mechanical procedures are described in a concise and systematic manner. Sufficient theory is provided to enable the reader to come to terms with the primary features of the methodology. In Part II, numerous applications of these procedures are described. These applications provide extensive consideration of highly topical and interesting modern chemistry, and also illustrate aspects of the methodology. Part III, which is new in the English edition, is written by Professor Richard D. Harcourt. To provide a fully balanced approach to the subject, this part provides valence bond descriptions, and considerable attention is given to the use of Pauling three-electron bonds and increased valence structures. Relevant valence-bond concepts are reviewed briefly in the first chapters of Part III. Quantum Mechanical Methods in Main-Group Chemistry provides an invaluable link between computational quantum chemical techniques and practical, modern chemistry. As such, it is an important resource for both the advanced undergraduate and postgraduate student, and also for the more experienced researcher.

Author Biography

Thomas Matthias Klapötke is a German inorganic chemist. He was Professor of Inorganic Chemistry at University of Glasgow from 1992 to 1997. Since 1997, he has been Professor of Inorganic Chemistry at the Ludwig Maximilian University of Munich. Axel Schulz is the author of Quantum Chemical Methods in Main-Group Chemistry published by Wiley.

Table of Contents

Series Preface	ix	(2)
Preface	xi	(2)
Acknowledgements	xiii	(2)
Units and Conversion Factors	xv
PART I THEORETICAL BACKGROUND OF AB INITIO CALCULATIONS	5	(120)
1 Quantum Mechanical Basics	5	(32)
1.1 Nomenclature, Atomic Units and Symbols	5	(3)
1.1.1 Nomenclature	5	(2)
1.1.2 Atomic units	7	(1)
1.2 Quantum Mechanical Postulates (in the Schrodinger Concept)	8	(4)
1.3 The Hydrogen Atom	12	(8)
1.3.1 Splitting degeneracy	15	(5)
1.4 The Pauli Exclusion Principle	20	(2)
1.5 Heisenberg's Uncertainty Principle	22	(3)
1.6 The Variation Principle	25	(1)
1.7 The Schrodinger Equation of a Multi-electron System	26	(2)
1.8 The Born-Oppenheimer Approximation	28	(3)
1.9 The Physical Nature of the Chemical Bond	31	(6)
2 SCF Calculations	37	(24)
2.1 The Hartree-Fock Method	37	(4)
2.2 The Roothaan-Hall Method	41	(2)
2.3 Closed-and Open-shell Systems	43	(2)
2.4 Stability of the Wave Function	45	(1)
2.5 The General Procedure of an ab initio Program	46	(3)
2.6 Minimization Strategies	49	(12)
3 The Electron Correlation	61	(15)
3.1 Post-HF Methods-Explicit Consideration of the Electron Correlation	61	(8)
3.1.1 Configuration interaction (CI)	61	(3)
3.1.2 MPhiller-Plesset perturbation theory	64	(3)
3.1.3 Coupled-cluster theory	67	(2)
3.2 Density Functional Theory	69	(3)
3.3 A Comparison of ab initio Methods and Their Limitations	72	(4)
4 Relativistic Effects	76	(7)
4.1 Kinematic Effects	76	(1)
4.2 Spin-Orbit Coupling	76	(1)
4.3 The Impact of Relativistic Effects	77	(3)
4.3.1 Silver and gold	78	(1)
4.3.2 The aurophilicity of gold	78	(1)
4.3.3 Mercury	79	(1)
4.4 The Pseudopotential Method	80	(3)
5 Normal Coordinates and Frequency Analysis	83	(16)
5.1 Calculation of the Harmonic Vibrational Frequencies	83	(6)
5.2 Thermodyamics	89	(4)
5.3 Intrinsic Stability, Reaction Path and Intrinsic Reaction Coordinates	93	(6)
6 Population Analysis	99	(6)
6.1 Natural Population Analysis (NPA)	99	(3)
6.2 Comparison between NPA and Mulliken Population Analysis	102	(1)
6.3 Bond Order	103	(2)
6.3.1 NLMO bond order (after Reed and Schleyer)	103	(2)
7 Basis Sets	105	(14)
7.1 Slater versus Gauss Functions	105	(4)
7.2 Minimal Basis Sets	109	(2)
7.3 Extended Basis Sets	111	(4)
7.4 The Basis Set Superposition Error	115	(4)
References	119	(6)
PART II APPLIED COMPUTATIONAL QUANTUM CHEMISTRY	125	(92)
8 Group 1	125	(10)
8.1 Superalkalis	125	(4)
8.2 Poly-lithium Clusters	129	(1)
8.3 Ammonia and Lithiated Ammonia	130	(2)
8.4 Hypervalency and Hypercoordination	132	(3)
9 Group 2	135	(8)
9.1 Alkaline Earth Hydrides	135	(2)
9.2 Alkaline Earth Dihalides	137	(2)
9.3 The Laplacian of the Electron Density for the MX(2) Molecules (M=Ca, Sr, Ba; X=H, F)	139	(4)
10 Group 13	143	(6)
10.1 The B-N Bond of Classical Donor-Acceptor Complexes	143	(3)
10.2 The Stability of the Hydrides and Halogenides of Group 13	146	(3)
11 Group 14	149	(18)
11.1 Pie Bonding in Group 14	149	(3)
11.2 Stability of Inorganic and Organic Pb(II) and Pb(IV) Compounds	152	(8)
11.3 Relativistic Effects in Group 14	160	(2)
11.4 Hyperconjugation, Anomeric Effect and Bohlmann Effect	162	(5)
12 Group 15	167	(14)
12.1 The Oxides of Nitrogen: Nitrosyl Azide, N(4)O	167	(3)
12.2 Covalent Azides	170	(7)
12.3 Nitrosyl Trifluoride, ONF(3)	177	(2)
12.4 The Structures of Radical Cations R(2)N-NR(2)(+)	179	(2)
13 Group 16	181	(14)
13.1 The NBO Analysis of SO(2) and SO(3)	181	(1)
13.2 Selenium-Nitrogen Compounds: the Cation [(SeCl(2))(2)N](+)	182	(5)
13.3 Selenium-Nitrogen Compounds: the Cation [(SeCl)(2)N](+)	187	(4)
13.4 The Hexamethylchalcogens, Me(6)E (E=S, Se, Te)	191	(1)
13.5 Protonated Hydrogen Sulfide: the Pentacoordinated Sulfonium Trication SH(5)(3+)	191	(1)
13.6 The Dihalogenodimethylselenium Compounds, Me(2)SeX(2) (X=F, Cl, Br, I, At)	192	(3)
14 Group 17	195	(6)
14.1 Interhalogen Cations	195	(2)
14.2 The Structure of CrF(6)	197	(4)
15 Group 18	201	(10)
15.1 Dihelium	201	(1)
15.2 Neutral Helium Compounds: HeBeO	201	(3)
15.3 Xenondifluoride	204	(3)
15.4 Nitrogen Compounds of the Noble Gases	207	(2)
15.5 Gold Compounds of the Noble Gases	209	(2)
References	211	(6)
PART III QUALITATIVE VALENCE BOND DESCRIPTIONS OF THE ELECTRONIC STRUCTURES OF SOME ELECTRON-RICH MOLECULES, USING INCREASED-VALENCE THEORY	217	(34)
16 Increased-valence Structures	217	(34)
16.1 Introduction	217	(1)
16.2 The One-electron bond	218	(1)
16.3 The Electron-pair Bond	218	(2)
16.4 The Three-electron Bond, or Three-electron Half-bond: Theory and Examples	220	(4)
16.4.1 Theory	220	(1)
16.4.2 Examples	221	(3)
16.5 Two Lone Pairs of Electrons; Non-bonded Repulsions	224	(1)
16.6 Four-electron Three-center Bonding Units	224	(2)
16.7 Increased-valence Structures Obtained by Spin-pairing the Odd-electron of a Three-electron Bond with the Odd-electron of an Atom	226	(5)
16.7.1 Examples: FO(2), FO(2)F and FO(2)NO	228	(2)
16.7.2 Example: O(3)	230	(1)
16.8 Increased-valence Structures Obtained by Spin-pairing the Anti-bonding Electrons of Two Three-electron Bond Structures	231	(3)
16.8.1 Examples: I(4)(2-), ONNO	232	(1)
16.8.2 O(4) and S(2)I(4)(2+)	233	(1)
16.9 Increased-valence Structures Obtained by Delocalization of a Non-bonding Electron into a Localized Bonding MO	234	(6)
16.9.1 Examples: FO(2)F, O(3), I(4)(2-), N(2)O, and NO(2)	235	(1)
16.9.2 Example: O(2)N-NO(2)	235	(4)
16.9.3 Examples: O(2)N-NO and ON-NO	239	(1)
16.9.4 NO(3), ONOO, ONONO(2), and ONOONO	239	(1)
16.10 Delocalization of a Non-bonding Electron into an Antibonding LMO	240	(1)
16.11 Increased-valence Structures for Four-electron Three-centre Bonding Units: Further Details	241	(3)
16.11.1 Increased-valence structures and orthogonal three-centre MOs	242	(1)
16.11.2 Increased-valence structures and donor-acceptor complexes	243	(1)
16.12 Gas-phase Nucleophilic Substitution Reactions	244	(2)
16.13 Hydrogen Bonding, Increased-valence Structure, and Approximate Molecular Orbital Theory	246	(1)
16.14 NO + NCO (XXX) N(2)O + CO and NO + NCO (XXX) N(2) + CO(2)	247	(2)
16.15 Six-electron Five-center Bonding	249	(1)
16.16 Conclusions	250	(1)
References	251	(4)
Index	255