ELECTRONIC ABSORPTION SPECTRA AND GEOMETRY OF ORGANIC MOLECULES
CONTENTS 1 GENERAL INTRODUCTION 1 1 GENERAL REMARKS 1 2 ELECTROMAGNETIC RADIATION 1 3 INTERACTION BETWEEN RADIATION AND MATTER 1 4 ENERGY RANGES 1 5 SPECTROSCOPIC TRANSITIONS 1 5 1 INDUCED ABSORPTION AND EMISSION 1 5 2 SPONTANEOUS EMISSION 1 5 3 NET ABSORPTION AND EMISSION 1 6 RELAXATION TIMES 1 7 LAWS OF LIGHT ABSORPTION 1 8 BORN–OPPENHEIMER APPROXIMATION 1 9 LINE WIDTH 1 10 TIME SCALES 1 11 INTENSITY OF SPECTRAL LINES FURTHER READING PROBLEMS 2 MOLECULAR SYMMETRY 2 1 SYMMETRY ELEMENTS AND SYMMETRY OPERATIONS 2 1 1 ROTATIONS 5HÀHFWLRQV 5RWDWLRQ5HÀHFWLRQ 2 1 4 CENTRE OF INVERSION 2 2 MULTIPLICATION OF SYMMETRY OPERATIONS 2 3 GROUP 2 3 1 MULTIPLICATION TABLE 2 3 2 SYMMETRY CLASS 2 4 THE POINT GROUP OF MOLECULES 2 5 EXAMPLES OF POINT GROUP ASSIGNMENTS 2 6 APPLICATIONS OF SYMMETRY 2 6 1 OPTICAL ACTIVITY 2 6 2 POLARITY 2 7 MATRIX REPRESENTATION OF GROUPS 2 8 THE CONCEPT OF REPRESENTATION 2 9 WIDENING THE BASES FOR REPRESENTATIONS 2 10 IRREDUCIBLE REPRESENTATIONS 2 11 CHARACTER TABLES 2 12 REDUCTION FORMULA 2 13 DIRECT PRODUCT OF REPRESENTATIONS 2 14 CORRELATION TABLES 2 15 DERIVATION OF THE CHARACTER TABLES 2 15 1 CONSTRUCTION OF THE CHARACTER TABLE – AN EXAMPLE 2 16 QUANTUM MECHANICAL INTEGRALS 3 ROTATIONAL SPECTROSCOPY 3 1 INTRODUCTION 3 2 PRINCIPAL MOMENTS OF INERTIA &ODVVL¿FDWLRQRI5RWRUV 3 3 DIATOMIC RIGID ROTOR 3 3 1 INTENSITY OF THE SPECTRAL LINES 3 3 2 SPECTRUM OF A RIGID ROTOR 3 4 DIATOMIC NON-RIGID ROTOR 3 4 1 SPECTRUM OF A NON-RIGID ROTOR 3 5 LINEAR POLYATOMIC MOLECULES 3 6 CLASSICAL MECHANICS TREATMENT OF ROTATION 3 7 NON-LINEAR POLYATOMIC MOLECULES 3 7 1 RIGID SYMMETRIC TOP MOLECULES 3 7 2 NON-RIGID SYMMETRIC TOP MOLECULES 3 7 3 ASYMMETRIC TOP MOLECULES 3 8 EFFECT OF NUCLEAR SPIN 3 9 INVERSION PHENOMENON 3 10 THE STARK EFFECT 3 10 1 SECOND ORDER STARK EFFECT 3 11 APPLICATIONS 3 12 EXPERIMENTAL CONSIDERATIONS 4 INFRARED SPECTROSCOPY 4 1 INTRODUCTION 4 2 SIMPLE HARMONIC OSCILLATOR 4 2 1 INFRARED ACTIVE BANDS 4 3 THE ANHARMONIC OSCILLATOR 4 3 1 HOT BANDS AND OVERTONES 4 3 2 SELECTION RULES 4 4 VIBRATIONS OF A POLYATOMIC MOLECULE &ODVVL¿FDWLRQRIWKH1RUPDO9LEUDWLRQV 4 4 2 SPECTRAL ACTIVITY: GROUP THEORETICAL APPROACH 4 5 SPECTRA OF SOME TRIATOMIC MOLECULES 4 5 1 FERMI RESONANCE 4 6 GROUP FREQUENCIES 4 6 1 COUPLED VIBRATIONS 4 6 2 INTERPRETATION OF SPECTRA 4 7 VIBRATION – ROTATION SPECTROSCOPY 4 7 1 THE VIBRATING ROTOR 4 7 2 BAND CONTOURS IN GAS PHASE SPECTRA 4 7 3 LINEAR POLYATOMIC MOLECULES 4 7 4 SYMMETRIC TOP MOLECULES 4 7 5 SPHERICAL TOP MOLECULES 4 7 6 EFFECT OF NUCLEAR SPIN 4 7 7 APPLICATIONS 4 8 EXPERIMENTAL ASPECTS 4 8 1 DISPERSIVE INFRARED SPECTROMETER 4 8 2 FOURIER TRANSFORM INFRARED SPECTROMETER 4 8 3 DESCRIPTION OF THE SPECTROMETER 4 8 4 ADVANTAGES 4 8 5 SAMPLING TECHNIQUES 4 9 STRUCTURE OF SMALL MOLECULES 4 9 1 TRIATOMIC MOLECULES 4 9 2 TETRATOMIC MOLECULES 4 9 3 PENTATOMIC MOLECULES 4 9 4 A GENERAL EXAMPLE 4 10 APPLICATIONS IN COORDINATION CHEMISTRY 4 10 1 AQUO COMPLEXES 4 10 2 AMMINE COMPLEXES 4 10 3 NITRITE COMPLEXES 4 10 4 THIOCYANATO COMPLEXES 4 10 5 COMPLEXES OF SULFOXIDES 4 10 6 METAL CARBONYLS 4 10 7 NITRATO COMPLEXES 4 10 8 SULPHATO COMPLEXES 4 10 9 METAL-LIGAND VIBRATIONS 4 11 SPECTRA OF ORGANIC COMPOUNDS 4 11 1 ASSIGNMENT OF FREQUENCIES 4 11 2 ANALYSIS OF THE INFRARED SPECTRA 4 11 3 HYDROGEN BONDING 5 RAMAN SPECTROSCOPY 5 1 THE RAMAN EFFECT 5 2 DESCRIPTION OF RAMAN EFFECT 5 3 BASIC PRINCIPLE 5 4 SELECTION RULES 5 5 DEPOLARIZATION RATIO 5 6 QUANTITATIVE ANALYSIS 5 7 VIBRATIONAL RAMAN SPECTRA 5 8 ROTATIONAL RAMAN SPECTROSCOPY 5 9 SYMMETRIC TOP MOLECULES 5 10 VIBRATION-ROTATION RAMAN SPECTROSCOPY 5 11 APPLICATIONS OF RAMAN SPECTROSCOPY 5 12 RESONANCE RAMAN EFFECT 5 13 SURFACE-ENHANCED RAMAN SCATTERING 5 14 EXPERIMENTAL CONSIDERATIONS 5 14 1 SOURCE 5 14 2 SAMPLE OPTICS 5 14 3 SPECTROMETER 5 14 4 SAMPLING PROCEDURE 5 15 NON-LINEAR RAMAN EFFECTS 6 ELECTRONIC SPECTROSCOPY OF ATOMS 6 1 THE QUANTUM NUMBERS 6 2 ATOMIC SPECTRUM 6 2 1 POPULATION FACTORS 6 2 2 SELECTION RULES 6 2 3 QUANTUM MECHANICAL FORMULATION OF SELECTION RULES 6 2 4 HYDROGEN SPECTRUM 6 2 5 HYDROGEN-LIKE IONS 6 2 6 SPIN-ORBIT COUPLING 6 3 TERM SYMBOL (OHFWURQLF&RQ¿JXUDWLRQ 6 4 1 SHELLS AND SUBSHELLS 6 5 SPECTRA OF ALKALI METAL ATOMS 6 5 1 FINE STRUCTURE 6 6 THE SPECTRUM OF HELIUM 6 7 SPECTRA OF MANY-ELECTRON ATOMS 6 7 1 RUSSELL-SAUNDERS COUPLING +XQG¶V5XOHV 6 7 3 RACAH PARAMETERS 6 7 4 JJ-COUPLING 6 8 THE EFFECTS OF MAGNETIC AND ELECTRIC FIELDS 6 8 1 NORMAL ZEEMAN EFFECT 6 8 2 THE ANOMALOUS ZEEMAN EFFECT 6 8 3 THE STARK EFFECT 7 ELECTRONIC SPECTROSCOPY 7 1 INTRODUCTION 7 2 ORGANIC POLYATOMIC MOLECULES 7 2 1 N P* TRANSITIONS 7 2 2 N S* TRANSITIONS 7 2 3 S S* TRANSITIONS 7 2 4 P P* TRANSITIONS 7 3 CONJUGATED DIENES 7 3 1 A, B-UNSATURATED KETONES AND ALDEHYDES 7 4 AROMATIC COMPOUNDS 7 5 DIATOMIC MOLECULES 7 5 1 ELECTRONIC TRANSITIONS 7 5 2 DISSOCIATION AND PREDISSOCIATION 7 5 3 TERM SYMBOLS FOR LINEAR MOLECULES 7 5 4 SELECTION RULES 7 5 5 SPECTRUM OF MOLECULAR HYDROGEN 7 6 BAND INTENSITY 7 6 1 MOLAR ABSORPTIVITY 7 6 2 TRANSITION PROBABILITY 7 7 VIBRONIC TRANSITIONS 7 7 1 FRANCK-CONDON FACTOR 7 8 TRANSITION METAL COMPLEXES 7 8 1 CRYSTAL FIELD SPLITTING 7 8 2 HIGH SPIN-LOW SPIN COMPLEXES 7 8 3 SPLITTING OF D-ORBITALS IN LOWER SYMMETRIES 7 8 4 ORGEL DIAGRAMS 7 8 5 TANABE-SUGANO DIAGRAMS 7 8 6 JAHN-TELLER EFFECT 7 8 7 COMPLEXES OF D 1 AND D 9 METAL IONS 7 8 8 COMPLEXES OF D 2 AND D 8 METAL IONS 7 8 9 COMPLEXES OF D 3 AND D 7 METAL IONS 7 8 10 COMPLEXES OF D 4 AND D 6 METAL IONS 7 8 11 COMPLEXES OF D 5 METAL IONS 7 8 12 SPIN-STATE CROSSOVER SYSTEMS 7 8 13 GEOMETRICAL ISOMERS 7 8 14 SPECTROCHEMICAL SERIES 7 8 15 NEPHELAUXETIC SERIES 7 8 16 SELECTION RULES TO SPECTRA OF TRANSITION METAL COMPLEXES 7 8 17 CHARGE-TRANSFER TRANSITIONS 7 9 EXPERIMENTAL METHODS 7 9 1 SPECTROMETER 7 9 2 SAMPLING PROCEDURE 8 OPTICAL ROTATORY DISPERSION AND CIRCULAR DICHROISM 8 1 OPTICAL ACTIVITY 8 2 BASIC PRINCIPLES 8 3 OPTICAL ROTATORY DISPERSION 8 4 CIRCULAR DICHROISM 8 5 COTTON EFFECT 8 6 SELECTION RULES 8 6 1 THE MAGNETIC TRANSITION MOMENT 8 6 2 SOME EXAMPLES 8 7 APPLICATIONS 8 8 SPECTROPOLARIMETER 8 8 1 MEASUREMENT OF ORD 9 FLUORESCENCE SPECTROSCOPY 9 1 JABLONSKI DIAGRAM 9 2 NONRADIATIVE DECAY 9 3 FLUORESCENCE 9 3 1 OTHER TYPES OF FLUORESCENCE 9 4 PHOSPHORESCENCE 9 5 CHARACTERISTICS OF LUMINESCENCE 9 6 X-RAY FLUORESCENCE 9 7 FLUORESCENCE LIFETIME AND QUANTUM YIELD 9 8 QUENCHING 9 8 1 DYNAMIC QUENCHING 9 9 APPLICATIONS 9 10 EXPERIMENTAL ASPECTS 6SHFWURÀXRURPHWHU 9 10 2 PHOSPHORIMETER 10 PHOTOELECTRON SPECTROSCOPY 10 1 PHOTOIONIZATION PROCESS 10 1 1 ENERGY CONSIDERATION 10 2 IONIZATION ENERGIES RRSPDQ¶V7KHRUHP 10 4 SPECTRUM OF DINITROGEN 10 5 SPECTRUM OF DIOXYGEN 10 5 1 SPECTRUM OF CORE ELECTRONS 10 6 SPIN-ORBIT COUPLING 10 7 X-RAY PHOTOELECTRON SPECTROSCOPY 10 8 AUGER ELECTRON SPECTROSCOPY 10 9 ELECTRON ENERGY LOSS SPECTROSCOPY 10 10 APPLICATIONS 10 11 EXPERIMENTAL CONSIDERATIONS 11 NUCLEAR MAGNETIC RESONANCE 11 1 NUCLEAR MAGNETISM 11 1 1 EFFECT OF MAGNETIC FIELD 11 1 2 RESONANCE PHENOMENA 11 2 CLASSICAL DESCRIPTION OF NMR 11 2 1 LARMOR FREQUENCY 11 2 2 MEASUREMENT OF SPECTRA 11 3 THE CHEMICAL SHIFT 11 3 1 ORIGIN 11 3 2 SIGNAL INTEGRATION 11 3 3 MEASUREMENT OF CHEMICAL SHIFT 11 3 4 REFERENCE COMPOUND 11 3 5 CHEMICAL SHIFTS OF DIFFERENT GROUPS 11 4 FACTORS AFFECTING THE CHEMICAL SHIFT 11 4 1 LOCAL DIAMAGNETIC SHIELDING 11 4 2 ANISOTROPY OF CHEMICAL BOND 11 4 3 HYDROGEN BONDING EFFECT 11 5 SPIN-SPIN COUPLING 11 5 1 EQUIVALENT NUCLEI 11 5 2 LABELLING SPIN SYSTEMS 11 6 MULTIPLET PATTERN OF SPIN 1/2 NUCLEI 11 6 1 SPECTRA OF AX2 AND AX3 SPIN SYSTEMS 11 6 2 SPECTRUM OF AMX SPIN SYSTEM 11 6 3 SPECTRUM OF A M X N SPIN SYSTEM 11 7 SCALAR COUPLING CONSTANTS 11 7 1 VICINAL COUPLING 11 8 STRONGLY COUPLED NUCLEI 11 9 EXPERIMENTAL METHODS 11 9 1 CONTINUOUS WAVE METHOD 11 9 2 PULSED FOURIER TRANSFORM METHOD 11 9 3 ADVANTAGES OF FT-NMR 11 9 4 SAMPLING PROCEDURE 11 10 DYNAMIC EFFECTS IN NMR SPECTRA 11 10 1 BARRIER TO INTERNAL ROTATION 11 10 2 FLUXIONAL MOLECULES 11 10 3 PROTON EXCHANGE 11 11 SPECTRA OF 13C, 19F AND 31P NUCLEI 11 11 1 13C NMR 11 11 2 13C CHEMICAL SHIFTS 11 11 3 13C—1H COUPLING CONSTANTS 11 11 4 19F NMR 11 11 5 31P NMR 11 12 SPIN DECOUPLING 11 12 1 BROAD BAND DECOUPLING 11 12 2 OFF-RESONANCE DECOUPLING 11 13 THE NUCLEAR OVERHAUSER EFFECT 11 14 DETERMINING MULTIPLICITIES 11 14 1 DEPT SPECTRA 11 15 RELAXATION PROCESSES 11 15 1 SPIN-LATTICE RELAXATION 11 15 2 SPIN-SPIN RELAXATION 11 15 5 NUCLEAR QUADRUPOLE RELAXATION 11 16 SHIFT REAGENTS 11 17 SOLID STATE NMR 11 17 1 MAGIC ANGLE SPINNING 11 18 2D NMR SPECTROSCOPY 11 18 1 THE PRINCIPLES OF 2D NMR 11 18 2 COSY 11 18 3 HETCOR 12 ELECTRON SPIN RESONANCE 12 1 ORIGIN OF ESR SIGNALS 12 2 G-FACTOR 12 3 INTERACTION OF MAGNETIC DIPOLES WITH MICROWAVE RADIATION 12 3 1 RELAXATION PROCESSES +\SHU¿QH6SOLWWLQJ +\SHU¿QH6SOLWWLQJIURP3URWRQV 12 5 1 SINGLE SET OF EQUIVALENT PROTONS 12 5 2 MULTIPLE SETS OF EQUIVALENT PROTONS 2ULJLQRI+\SHU¿QH,QWHUDFWLRQ 12 7 1 DIPOLAR INTERACTION 12 7 2 FERMI CONTACT INTERACTION 12 7 3 SPIN POLARIZATION 12 8 ANISOTROPIC SYSTEMS 12 9 EXPERIMENTAL CONSIDERATIONS 12 9 1 ESR SPECTROMETER 12 9 2 SAMPLING PROCEDURE 12 9 3 SPECTRA 12 9 4 DETERMINATION OF G-VALUE 12 10 TRIPLET STATE 12 10 1 SPIN TRANSITIONS IN TRIPLET STATE 12 10 2 ZERO-FIELD SPLITTING 12 10 3 SPECTRUM OF NAPHTHALENE TRIPLET 12 11 COMPLEXES OF TRANSITION METAL IONS 12 11 1 CHARACTERISTICS OF THE SPECTRA 12 11 2 COMPLEXES OF 3D 1 AND 3D 9 METAL IONS 12 11 3 COMPLEXES OF 3 D 5 METAL IONS 12 12 DOUBLE RESONANCE TECHNIQUES 12 12 1 ELECTRON-NUCLEAR DOUBLE RESONANCE 12 13 APPLICATIONS 13 NUCLEAR QUADRUPOLE RESONANCE 13 1 INTRODUCTION 13 2 NUCLEAR QUADRUPOLE MOMENT 13 3 FUNDAMENTALS 13 3 1 ASYMMETRY PARAMETER 13 4 NUCLEAR QUADRUPOLE TRANSITIONS 13 4 1 AXIALLY SYMMETRIC MOLECULES 13 4 2 AXIALLY NON-SYMMETRIC MOLECULES 13 5 EFFECT OF MAGNETIC FIELD 13 6 APPLICATIONS 13 7 EXPERIMENTAL ASPECTS 14 MÖSSBAUER SPECTROSCOPY 14 1 INTRODUCTION 14 2 PRINCIPLES 14 3 EXPERIMENTAL DETAILS 14 3 1 LINE WIDTH 14 3 2 RECOIL ENERGY 14 4 MÖSSBAUER SPECTRAL PARAMETERS 14 4 1 ISOMER SHIFT 14 4 2 ELECTRIC QUADRUPOLE INTERACTIONS 14 5 IRON 14 5 1 SPIN STATE CROSSOVER SYSTEMS 14 5 2 APPLICATIONS 14 7 EFFECT OF APPLIED MAGNETIC FIELD 15 X-RAY ABSORPTION SPECTROSCOPY 15 1 INTRODUCTION 15 2 X-RAY EMISSION SPECTRUM 15 3 X-RAY ABSORPTION SPECTRUM 15 3 1 ABSORPTION OF X-RAYS 15 4 XANES AND EXAFS 15 5 THEORY 15 6 APPLICATIONS 15 7 EXPERIMENTAL ASPECTS 16 MOLECULAR MASS SPECTROMETRY 16 1 THE PRINCIPLE 16 2 INTERPRETATION OF MASS SPECTRA 16 3 TYPES OF IONS PRODUCED IN A MASS SPECTROMETER 16 3 1 FRAGMENT IONS 16 3 2 THE MOLECULAR ION 16 3 3 METASTABLE IONS 16 3 4 EVEN-ELECTRON RULE 16 4 NITROGEN RULE 16 5 MCLAFFERTY REARRANGEMENT 16 6 ISOTOPE PATTERN ,GHQWL¿FDWLRQRI&RPSRXQGV 16 8 ACCURATE MASS MEASUREMENT 16 9 APPLICATIONS OF MASS SPECTROMETRY 16 10 IONIZATION TECHNIQUES 16 10 1 ELECTRON IMPACT (EI) 16 10 2 CHEMICAL IONIZATION (CI) 16 10 3 FIELD IONIZATION (FI) 16 10 4 FIELD DESORPTION (FD) 16 10 5 ELECTROSPRAY IONIZATION (ESI) 16 10 6 MATRIX-ASSISTED LASER DESORPTION IONIZATION (MALDI) 16 10 7 FAST ATOM BOMBARDMENT (FAB) 16 11 MASS SPECTROMETER 16 11 1 SINGLE FOCUSING MASS SPECTROMETER 16 11 2 TIME OF FLIGHT MASS SPECTROMETER 16 11 3 QUADRUPOLE MASS SPECTROMETER 16 11 4 DOUBLE FOCUSING MASS SPECTROMETER