ELECTRICAL CONDUCTANCE IN ORGANIC SOLIDS

The work is divided along three general lines: a) the study of transport of carriers injected into insulating (or poorly conducting) solids by an electron gun, b) electrical measurements on highly conducting ion-radical salts, and c) study of carrier transport in some amorphous systems. During this quarter, the work was centered on the first of these objectives. To this end, mobility and lifetime measurements for electrons and holes was made on a series of single-crystal anthracene specimens. Good mobility data was obtained at room temperature on these samples, but severe trappings limited the lifetimes to about 50 microseconds. An attempt is being made to obtain crystals of higher purity and less trapping in order to extend the measurements to lower temperatures. Initial efforts to observe carrier transport in Ni02 (an inorganic narrow-band semiconductor with many similarities to the molecular crystal organic system) were particularly encouraging. Significant multiplications, resulting in sufficient carrier generation, was observed in single-crystal samples. Sponsored in part by the DARPA.