Wollrab / Loebl Rotational Spectra and Molecular Structure

Physical Chemistry: A Series of Monographs
1. Auflage 2013
ISBN: 978-1-4831-9485-1
Verlag: Elsevier Science & Techn.
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, 484 Seiten, Web PDF

Physical Chemistry, A Series of Monographs: Rotational Spectra and Molecular Structure covers the energy levels and rotational transitions. This book is divided into nine chapters that evaluate the rigid asymmetric top molecules and the nuclear spin statistics for asymmetric tops. Some of the topics covered in the book are the asymmetric rotor functions; rotational transition intensities; classes of molecules; nuclear spin statistics for linear molecules and symmetric tops; and classical appearance of centrifugal and coriolis forces. Other chapters deal with the energy levels and effects of centrifugal distortion, as well as the internuclear distance and moments of inertia. The discussion then shifts to the coriolis coupling effects on rotational constants and the perturbation treatment of vibration-rotational Hamiltonian. The last chapter is devoted to the examination of origin of the quadrupole interaction. The book can provide useful information to chemists, physicists, electrical engineers, students, and researchers.

Autoren/Hrsg.

Wollrab, James E.

Loebl, Ernest M.

Inhaltsverzeichnis

1;Front Cover;1
2;Rotational Spectra and Molecular Structure;4
3;Copyright Page;5
4;Table of Contents;10
5;Dedication;6
6;PREFACE;8
7;ACKNOWLEDGMENTS;9
8;Chapter 1. Rotational Spectra;18
8.1;1-1. Energy Levels and Rotational Transitions;18
8.2;1-2. Information Contained in Rotational Spectra;21
9;Chapter 2. Rigid Rotor;24
9.1;2-1. Introduction;24
9.2;2-2. Molecular Parameters;24
9.3;2-3. Classes of Molecules;30
9.4;2-4a. Rigid Linear Molecules;30
9.5;2-4b. Spectrum and Selection Rules;31
9.6;2-5a. Rigid Symmetric-Top Molecules;32
9.7;2-5b. Spectrum and Selection Rules;35
9.8;2-6a. Rigid Asymmetric-Top Molecules;36
9.9;2-6b. Matrix Elements of E(k);39
9.10;2-6c. Asymmetric Rotor Functions;41
9.11;2-6d. Selection Rules;44
9.12;2-6e. K Doubling in an Asymmetric Rotor;48
9.13;2-6f. Graphical Methods for Determining k and (A — C)/2;49
9.14;2-7. Rotational Transition Intensities;50
9.15;2-8. Statistical Weights;52
9.16;2-9. Nuclear Spin Statistics for Linear Molecules;54
9.17;2-10a. Nuclear Spin Statistics for Symmetric Tops;54
9.18;2-10b. Rotational Wave Functions;55
9.19;2-10c. Spin Wave Functions;55
9.20;2-11a. Nuclear Spin Statistics for Asymmetric Tops;57
9.21;2-11b. Rotational Wave Functions;57
9.22;2-11c. Spin Wave Functions;58
9.23;2-12a. Dipole Matrix Elements;59
9.24;2-12b. Dipole Matrix Elements for a Linear Molecule;61
9.25;2-12c. Dipole Matrix Elements for a Symmetric Rotor;62
9.26;2-12d. Dipole Matrix Elements for an Asymmetric Rotor;64
9.27;2-13. Transition Strengths and Approximate Wave Functions for Near Symmetric Tops;66
10;Chapter 3. Centrifugal Distortion, Coriolis Coupling, and Fermi Resonance;68
10.1;3-1. Introduction;68
10.2;3-2. Classical Appearance of Centrifugal and Coriolis Forces;69
10.3;3-3. Centrifugal Distortion in a Linear Molecule;71
10.4;3-4. Centrifugal Distortion in Symmetric Top Molecules;74
10.5;3-5. The Coriolis Coupling Constant;77
10.6;3-6a. /-Type Doubling in Linear Molecules;78
10.7;3-6b. Direct /-Type Transitions;82
10.8;3-7a. Degenerate Coriolis Splitting;83
10.9;3-7b. /-Type Doubling in Symmetric Top Molecules;86
10.10;3-7c. Energy Levels and Effects of Centrifugal Distortion;87
10.11;3-8. Dipole Matrix Elements and Selection Rules for /-Doubling;89
10.12;3-9. Fermi Resonance in Linear Molecules;90
10.13;3-10a. Nonrigid Effects in Asymmetric Rotors;92
10.14;3-10b. Perturbation Treatment of Vibration-Rotation Hamiltonian;93
10.15;3-10c. Interactions for Near Degeneracies;95
10.16;3-11. Coriolis Coupling Effects on Rotational Constants;97
10.17;3-12. Centrifugal Distortion in Asymmetric Tops;98
10.18;3-13. Fermi Resonance in Nonlinear Molecules;104
11;Chapter 4. Molecular Structure;105
11.1;4-1. Internuclear Distances and Moments of Inertia;105
11.2;4-2. ro Structure;107
11.3;4-3. rs Structure;109
11.4;4-4a. Linear Molecules;110
11.5;4-4b. Comparison of ro and rs Structures for Linear Molecules;111
11.6;4-5. Off-Axis Substitution in a Symmetric Top;114
11.7;4-6a. Planar Asymmetric Tops;115
11.8;4-6b. Nonplanar Asymmetric Tops;116
11.9;4-7. Structure Determinations When All Atoms Are Not Isotopically Substituted;117
11.10;4-8a. Determination of Coordinates near Principal Axes : Linear Molecules;119
11.11;4-8b. Near Axis Coordinates in Asymmetric Tops;120
11.12;4-8c. Coordinates of Atoms near the COM in an Asymmetric Top with a Plane of Symmetry;121
11.13;4-9a. The Inertia Defect;122
11.14;4-9b. Planar Molecules;124
11.15;4-9c. Inertia Defect and Molecular Structure of Planar Molecules;124
11.16;4-9d. Inertia Defect in Nonplanar Molecules;125
11.17;4-10. Variation of Bond Length with Isotopic Substitution;127
11.18;4-11. Values and Limitations of the Average Structure;129
12;Chapter 5. Nuclear Quadrupole Coupling;131
12.1;5-1. Quadrupole Nuclei in Molecules;131
12.2;5-2. Origin of the Quadrupole Interaction;132
12.3;5-3. Matrix Elements of HQ;138
12.4;5-4. First-Order Quadrupole Energy;139
12.5;5-5. Second-Order Quadrupole Energy;148
12.6;5-6. Molecules with Two Quadrupole Nuclei;150
12.7;5-7. Molecules with Three Quadrupole Nuclei;154
12.8;5-8. Quadrupole Hyperfine Structure in Excited Vibrational States;157
12.9;5-9. Relative Intensities of Quadrupole Components;159
13;Chapter 6. Internal Rotation;162
13.1;6-la. Introduction;162
13.2;6-lb. Physical Models;162
13.3;6-lc. Potential Energy and Hindered Rotation;163
13.4;6-2. High Potential Barriers;167
13.5;6-3a. Energy Levels, Selection Rules, and Intensities for a High Barrier;168
13.6;6-3b. A Single Internal Rotor;168
13.7;6-3c. Two Equivalent Internal Rotors;171
13.8;6-4. The PAM for a Symmetric Top Molecule;175
13.9;6-5. The IAM for a Symmetric Top Molecule;180
13.10;6-6. PAM for Asymmetric Molecules with Symmetric Internal Rotors;184
13.11;6-7. IAM for Asymmetric Top Molecules;189
13.12;6-8. Low Barriers;195
13.13;6-9. Completely Asymmetric Molecules;200
13.14;6-10. Internal Rotation Barriers from Intensities;201
13.15;6-11. Internal Barriers from Vibration-Rotation Interactions;201
13.16;6-12. Excited Torsional States;202
13.17;6-13a. Coriolis Interactions and Internal Rotation in Symmetric Top Molecules;203
13.18;6-13b. Coriolis Interactions in Excited Torsional States.of Asymmetric Rotors;205
13.19;6-14. V6 Contributions to the Torsional Barrier;207
13.20;6-15. Internal Rotation and Nuclear Quadrupole Coupling;209
13.21;6-16a. Molecules with Two Equivalent Methyl Groups;211
13.22;6-16b. Kinetic Energy;211
13.23;6-17. Symmetric Tops with Three Methyl Groups;216
13.24;6-18. Rotational Isomerism;218
13.25;6-19. Barriers Determined from Rotational Spectra;219
14;Chapter 7. Inversion;220
14.1;7-1. Characteristics of the Inversion Motion;220
14.2;7-2. Properties of the Inversion Wave Functions;222
14.3;7-3. Inversion in Symmetric Top Molecules;224
14.4;7-4a. Some Potential Functions for the Twofold Inversion Barrier;225
14.5;7-4b. Morse-Stuckelberg Potential;226
14.6;7-4c. Dennison-Uhlenbeck Potential;226
14.7;7-4d. Rosen-Morse Potential;228
14.8;7-4e. Manning Potential;230
14.9;7-4f. Wall-Glocker Potential;231
14.10;7-4g. Newton-Thomas Potential;233
14.11;7-4h. Sutherland-Costain Potential;233
14.12;7-4i. Harmonic Oscillator Perturbed by a Gaussian Barrier;234
14.13;7-4j. Quartic Oscillator;238
14.14;7-4k. Mixed Harmonic-Quartic Potential;239
14.15;7-5. Inversion-Vibration Interactions;239
14.16;7-6. Reduced Mass for NH3-like Symmetric Tops;240
14.17;7-7. Rotational Dependence of Inversion Splittings in Symmetric Tops;241
14.18;7-8. \K\ = 3 Inversion Transitions in Ammonia;242
14.19;7-9a. Inversion in Asymmetric Tops;243
14.20;7-9b. Selection Rules for Asymmetric Tops;244
14.21;7-9c. Types of Barriers;245
14.22;7-9d. Application of Symmetric Top Potential Functions to Asymmetric Tops;246
14.23;7-9e. Reduced Mass for Inversion in an Asymmetric Top;246
14.24;7-9f. Rotational Dependence of the Inversion Splittings in an Asymmetric Rotor;249
14.25;7-10. Inversion-Inversion Coupling;249
14.26;7-11. Inversion and Internal Rotation—The Methyl Amines;251
14.27;7-12a. Inversion in Near-Planar Molecules;253
14.28;7-12b. Inertial Defect;254
14.29;7-12c. Satellites and Intensities;254
14.30;7-12d. Stark Effect;255
14.31;7-12e. Far Infrared Spectrum;256
14.32;7-12f. Variation of Rotational Constants with Vibrational State;256
14.33;7-13. Vibration-Rotation Interactions;258
15;Chapter 8. Stark Effect;261
15.1;8-1. Introduction;261
15.2;8-2. General Properties of the Stark Effect;262
15.3;8-3. Matrix Elements of He;263
15.4;8-4. First-Order Stark Effect;264
15.5;8-5. Second-Order Stark Effect;264
15.6;8-6. High Field Stark Effect and Higher-Order Perturbation Terms;267
15.7;8-7. Stark Effect for Near Degeneracies;270
15.8;8-8a. Stark Effect and Quadrupole Hyperfine Structure;271
15.9;8-8b. Weak Field with a Single Quadrupole Nucleus (µe « eqQ);273
15.10;8-8c. Strong Field with a Single Quadrupole Nucleus (µe » eqQ);277
15.11;8-8d. Intermediate Case (µe ˜ eqQ);278
15.12;8-8e. Near Degeneracies;279
15.13;8-9. Polarizability;279
15.14;8-10a. Stark Splittings and Relative Intensities;281
15.15;8-10b. .M = 0 Transitions;281
15.16;8-10c. .M = ±1 Transitions;283
15.17;8-1 Od. Intensities in the Presence of Hyperfine Structure;283
15.18;8-11a. Stark Effect in a Linear Molecule—OCS;284
15.19;8-11b. Stark Effect for an /-Type Doublet;286
15.20;8-11c. Stark Effect in a Symmetric Top Molecule—CH3F;288
15.21;8-11d. Stark Effect in an Asymmetric Rotor—CH3CHF2;290
15.22;8-11e. Stark Effect in a II Electronic State—NO;291
15.23;8-12. Stark Effect and Hindered Internal Motions;291
15.24;8-13. Dipole Moment Measurement Techniques;293
15.25;8-14. Stark Effects in Rapidly Varying Fields;296
15.26;8-15. Variation of µ with Isotopic Substitution and with Vibrational State;297
16;Chapter 9. Instrumentation;299
16.1;9-1. Spectroscopy in the Microwave Region;299
16.2;9-2. General Qualities of the Spectrometer;300
16.3;9-3a. Characteristics of Microwave Spectrometers;305
16.4;9-3b. Radiation Sources;306
16.5;9-3c. Source Stabilization;308
16.6;9-3d. Waveguide Stark Cell;311
16.7;9-3e. Modulation, Detection, and Display;312
16.8;9-3f. Frequency Measurements;317
16.9;9-3g. Millimeter and Submillimeter Techniques;318
16.10;9-4. Relative Intensity and Line Width Measurement;322
16.11;9-5. Parallel Plate Spectrometers;326
16.12;9-6. High Temperature and Molecular Beam Spectroscopy;327
16.13;9-7. Applications of Double-Resonance and Beam-Maser Spectrometers;329
16.14;9-8. Study of Free Radicals and Unstable Species;331
16.15;9-9. Zeeman Effect Spectrometers;332
17;Appendix 1: References;335
18;Appendix 2: Short Table of Physical Constants, Conversion Factors, and Waveguide Nomenclature;409
19;Appendix 3: Evaluation of E(k);410
20;Appendix 4: Derivation of the Hamiltonian for Treating the Vibration-Rotation Interaction Problem;416
21;Appendix 5: Derivation of the Inertial Defect;423
22;Appendix 6: Coupling of Angular Momentum Vectors;426
23;Appendix 7: The Van Vleck Transformation;428
24;Appendix 8: Internal Rotation Splittings for the IAM;431
25;Appendix 9: Barriers to Internal Rotation Determined by Microwave Spectroscopy;433
26;Appendix 10: Vanishing of Odd-Order Nondegenerate Stark Corrections;439
27;Appendix 11: Mathieu's Equation;440
28;Appendix 12: Perturbation Coefficients for the Internal Rotation Problem;444
29;Appendix 13: Molecular Zeeman Effect;457
30;Appendix 14: Stark Corrections for a Linear Molecule;464
31;AUTHOR INDEX;466
32;SUBJECT INDEX;481