Electronic excited state transport among molecules distributed randomly in a finite volume

Abstract

A theoretical study of electronic excited state transport among molecules randomly distributed in a finite volume is carried out. Two special cases of the general transport and trapping problem are treated. A truncated series expansion in powers in the chromophore density is used as an approximation for one component systems (i.e., donor–donor transport only). In two component systems of donors and traps, the Förster limit, in which transfer can occur only from donors to traps due to low donor concentrations, is solved exactly for a finite spherical volume. In both cases, the results presented demonstrate that time-dependent observables can be significantly altered in finite volume systems relative to infinite volume systems. These calculations have implications for the interpretation of experiments performed on real finite volume systems, e.g., energy transport among the chromophores of an isolated polymer chain.