Vibronic Structure in the Fluorescence Lifetimes and Quantum Yields of Aniline Vapor

摘要: Aniline vapor has a well‐resolved vibronic absorption spectrum in the region of first excited singlet transition. By means high‐resolution phase fluorimetry we have determined fluorescence lifetimes and quantum yields over from 300 to 275 nm with bandwidth 2.7 A. The emission was not resolved. Relative values at different wavelengths were measured directly while absolute estimated literature data. Quantum fluctuate between 0.3 0.6 reciprocal lifetime, 1 / τ, varies range (1.3 2.3) × 108 sec−1. 1 / τ shows sharply pointed minima whereas maxima all major peaks. calculated intersystems crossing rate constants kisc minimum these wavelengths. These features are interpreted terms symmetry selection rules for spin–orbit coupling.