Positronium and Iodine Reactions in Organic Solvents

Abstract

The quenching of o-Ps by iodine in various organic solvents is investigated. It is found that iodine acts as both a chemical quenching agent and a Ps formation inhibitor. The reaction between Ps and iodine is diffusion controlled. The annihilation lifetime of the formed Ps iodine compound (PsI2 or PsI) is estimated to be 0.4 nsec. The inhibition coefficient is calculated to be 20 mole−1 for iodine in hydrocarbon solvents and 5.0 mole−1 in oxyhydrocarbon solvents. After an investigation the high Ps quenching rates in iodine solutions cannot all be attributed to high values of the diffusion coefficient. The interaction between Ps and iodine must also be taken into consideration. Obviously, the formation of the charge-transfer complex of iodine plays an important role here.