ABSTRACT

By Josef Michl, Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, U.S.A.

1a Introduction 1b Electronic States 1b-1 Electronic Wave Functions 1b-2 Potential Energy Surfaces 1b-3 Vibrational Wave Functions 1b-4 Potential Energy Surface Shapes 1b-5 Singlet and Triplet States 1b-6 State Labels 1b-7 Jablonski Diagram 1b-8 Adiabatic Processes 1c Radiative Transitions 1c-1 Electromagnetic Radiation 1c-2 Absorption and Emission 1c-3 Transition Dipole Moment and Selection Rules 1c-4 Linear Polarization 1c-5 Circular Polarization 1c-6 Vibrational Fine Structure 1c-7 Vibronic Coupling 1d Non-Radiative Transitions 1d-1 Non-Born-Oppenheimer Terms 1d-2 Internal Conversion 1d-3 Intersystem Crossing 1d-4 Electron Transfer 1d-5 Energy Transfer 1e Excited State Kinetics

1a INTRODUCTION

The following is a short overview of the principles of photophysics. We start by providing a brief survey of electronic excited states in Section 1b. This material can be found in textbooks of quantum chemistry but we have directed it to the specific needs of those wishing to learn the fundamentals of photophysics. We then proceed to the description of radiative (Section 1c) and non-radiative (Section 1d) transitions between electronic states. Strictly speaking, the material of Section 1c belongs to the discipline of electronic spectroscopy at least as much as it belongs to photophysics, but it was felt that it would be useful to outline the basics here instead of referring the reader elsewhere. Section 1e deals with the procedures that are in common use for the analysis of photophysical and photochemical kinetic data.