Fractal-Like Exciton Kinetics in Porous Glasses, Organic Membranes, and Filter Papers

Abstract
We have measured the exciton (triplet) recombination (fusion, annihilation) characteristics of naphthalene-doped microporous materials. This technique yields the dynamic (spectral, fracton) dimension of the embedded naphthalene structure or the effective random-walk dimension of the porous network. Temperature studies separate the energetic and geometric features of the pore space. The geometric dynamic (spectral) dimensions are mostly between 1 and 2, i.e., fractal-like, and are consistent with previous results on the static (fractal or Euclidean) dimensions of the porous Vycor glass samples.