Energy Transfer by Resonance between Organic Molecules in Solution

Abstract

The probabilities P of the energy transfer by dipole-dipole interaction from excited pyrene to non-excited perylene in n -hexane were measured by a pulse method. The value of P was found to be approximately proportional to the relative diffusion coefficient D of both molecules above the value D of 3.5×10 ^-5 cm ² /sec and to D ^3/4 below that value of D . When D is large both molecules migrate so rapidly that they collide with each other before the excited donor transfers its energy to the acceptor by dipole-dipole interaction. Meanwhile, if D is small, the energy transfer by dipole-dipole interaction takes place from the donor to the distant acceptor before their collision. The experimental results were well analyzed by Yokota and Tanimoto's calculation.