Mobility and radiation yield of free electrons in liquid and crystalline isooctane

The drift mobility and radiation yield of shared pairs of the Gfi charges in liquid and solid isooctane have been measured by the ionizing radiation-induced electroconductivity method. It has been found that Gfi(0)=0.24/100 eV in solid isooctane at 150 K in zero electric field. To this value corresponds the most probable initial distance between the thermally excited electrons and ''their own'' positive ions b=140 A, which is higher than the previous reported value (B=90 A) in liquid isooctane. It is shown that transition from liquid to crystalline phase increases the following parameters: Gfi in the 5x103 V/cm (3.5 times), the product of mobility and free electron lifetime, drift mobility activation energy (from 0.06 to 0.5+-0.1 eV). The results are associated with the ordering of structure and increase of the free electron level in transition from liquid to crystal