AbstractThe use of pulsed laser excitation upon a series of 1‐vinylnaphthalene/methyl methacrylate co‐polymers in which the intramolecular chromophore concentration is varied over a wide composition range has allowed the individual rate constants governing intramolecular excimer formation to be determined at various temperatures between 205 and 295 K. Triple exponential functions are necessary for adequate description of the photophysical kinetics over the entire temperature range. It is proposed that the kinetic and temperature behavior is consistent with a kinetic scheme involving two kinetically distinct monomeric species and an excimer in which energy may be transferred from the second monomer M*2to the first monomer M*1which can interact with the excimer by a conventional migration mechan