The Electrical Conductivity of the Condensed Polynuclear Aromatic Compounds

Abstract

Abstract The electrical conductivity of the condensed polynuclear aromatic compounds; (1) isoviolanthrone, (2) isoviolanthrene, (3) violanthrone, (4) violanthrene, (5) ovalene, (6) pyranthrone, (7) pyranthrene, (8) meso-naphthodianthrone, (9) meso-naphthodianthrene, (10) anthanthrone and (11) anthanthrene,— has the character of a semi-conductor. The resistivity of these compounds can be expressed as ρ=ρ0 exp (Δε/2kT). The value of Δε and ρ at 15° were found as, (1) 0.75e.V., 5.7×109Ωcm., (2) 0.82 e. V., 8.4×1013Ωcm., (3) 0.78 e. V., 2.3×1010Ωcm., (4) 0.85 e.V., 2.1×1014Ωcm., (5) 1.13 e.V., 2.3×1015Ωcm., (6) 1.06 e.V., 3.9×1015Ωcm., (7) 1.07 e.V., 4.5×1016Ωcm., (8) 1.30 e.V., 1.5×1018Ωcm., (9) 1.2 e.V., 4.0×1018Ωcm., (10) 1.70 e.V., 7.7×1018Ωcm., (11) 1.67 e.V., 1.5×1019Ωcm.. The good reproducibility and non-hysteresis of the electrical conductivity for temperature suggests electronic conduction. As these organic compounds have a perfect molecular lattice, the possibility of impurity-level cannot be considered. For this reason the mechanism of the conduction is assumed to be that of the intrinsic semi-conductor