A microscopic diffusion model is presented for the determination of orthopositronium (o-Ps) lifetime in micellar solutions. Among other parameters, the lifetime density function depends on the o-Ps diffusion coefficient in the water phase. Orthopositronium diffusion coefficients are determined by fitting this lifetime density function to positron annihilation spectra obtained from 1 mol/dm3 solution of sodium dodecylsulphate (SDS) in D2O at different temperatures. The activation energy of the o-Ps diffusion in D2O obtained from an Arrhenius plot as Ea = 0.922 ± 0.103 eV indicates strong localization.
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry