Excited States

Excited States, Volume I reviews radiationless transitions, phosphorescence microwave double resonance through optical spectra in molecular solids, dipole moments in excited states, luminescence of polar molecules, and the problem of interstate interaction in aromatic carbonyl compounds. The book discusses the molecular electronic radiationless transitions; the double resonance techniques and the relaxation mechanisms involving the lowest triplet state of aromatic compounds; as well as the optical spectra and relaxation in molecular solids. The text also describes dipole moments and polarizabilities of molecules in excited electronic states; the luminescence characteristics of polar aromatic molecules; and the interstate interaction in aromatic aldehydes and ketones. Chemists and physical chemists will find the book invaluable.

Contenu

List of Contributors

Preface

Molecular Electronic Radiationless Transitions

I. Introduction

II. Early Work of Wentzel and Rice

III. Lewis, Franck, and Livingston

IV. Heavy Atom and Deuterium Effects

V. Continua and State Densities

VI. A Physical Model for Electronic Relaxation

VII. Some Simple Mathematical Models

VIII. More Advanced Mathematical Models

IX. Preparation and Evolution of the Initial State

X. Born-Oppenheimer Approximations

References

Double Resonance Techniques and the Relaxation Mechanisms Involving the Lowest Triplet State of Aromatic Compounds

I. Introduction

II. Origin of Zero-Field Splittings

III. Production of State of Spin Alignment by Light Absorption at Low Temperatures

IV. Phosphorescence Microwave Double Resonance Basic Equations

V. Experimental Determination of the Relative Intersystem Crossing Rates

VI. Assignment of Zero-Field Transitions and Phosphorescence Mechanisms

VII. Mechanism of the Intersystem-Crossing Process

VIII. Other Relaxation Processes Involving Triplet State

References

Optical Spectra and Relaxation in Molecular Solids

I. Introduction

II. The Electronic Spectrum of a Space-Fixed Molecule

III. Phonons and Excitons

IV. Exciton-Phonon Interactions in Neat Molecular Crystals

V. Mixed Crystals

VI. Broadening of Electronic Spectra in Molecular Solids

VII. Phonon Side Bands in Neat Molecular Crystal Spectra

VIII. Phonon Side Bands in the Spectra of Mixed Molecular Crystals

IX. Line Broadening in Mixed Crystals

. Phonon Side Bands and Linewidths: Summary and Experiments

XI. Coupling of Vibronic Levels of the Molecules in a Crystal

. Vibrational and Electronic Relaxation in Molecules: What Can Crystal Studies Contribute

XIII. Spin-Dependent Processes

References

Dipole Moments and Polarizabilities of Molecules in Excited Electronic States

I. Introduction

II. Effects of an External Electric Field on the Spectra of Molecules

III. The Solvent Dependence of the Wave Number of Optical Absorption and Emission

IV. Optical Anisotropy from Optically Induced Birefringence

References

Luminescence Characteristics of Polar Aromatic Molecules

I. Introduction

II. Monosubstituted Aromatics with Appended Electron-Donor Groups

III. Monosubstituted Aromatics with Appended Electron-Acceptor Groups

IV. Correlative Aspects of the Spectroscopy of Isoelectronic Monosubstituted Aromatics

V. Donor-Aromatic-Acceptor (D-Ar-A) Molecules

VI. Conclusion

References

Interstate Interaction in Aromatic Aldehydes and Ketones

I. Introduction

II. Intermediate Coupling. Vibronic Interaction between Nearby States

III. Weak Coupling. Vibronic Interaction between Well-Spaced States

IV. Strong Coupling. Vibronic Interaction between Closely Spaced States

V. Departure from the Born-Oppenheimer Approximation for Closely Spaced States

VI. Conclusion

References

Author Index

Subject Index