Ion mobility measurements in dielectric liquids

Mobilities have been determined by fitting theoretical current--time curves to experimental ones. The theoretical current--time curves were obtained by solving numerically the differential equations governing carrier motion during a mobility measurement.The current--time curves generated from the model are in good agreement with those obtained experimentally. The theoretical model that includes the effects of induced bulk liquid motion yields values of mobility that are significantly lower than those determined experimentally by use of inflection or ''half-steady-state'' points. Measurements made on purified n-hexane showed that a radiation pulse produces more than one slow carrier of each sign. When biphenyl was added to the sample, one negative and two positive species were observed. Our theoretical fits to experimental curves obtained from the irradiation of a 0.22M solution of biphenyl in n-hexane yields a mobility value for the negative species of 3.6times10-4 cm2 V-1center-dotsec-1. This negative species is believed to be the biphenylide anion