Comparison of optical scattering experiments and the quasi-crystalline approximation for dense media

The fractional volume dependence of the extinction rate in dense media is studied. Results from optical scattering experiments are compared with the theoretical extinction rate calculated by independent-scattering theory and the quasi-crystalline approximation (QCA). QCA takes into account the coherent interaction among scatterers in the vicinity of each other, as weighted by a pair distribution function. QCA is shown to be in good agreement with experimental data.