Techniques involving the use of high-intensity short-duration light pulses have been applied t o the study of the kinetics of photoconductivity in films of metal-free phthalocyanine. These experiments, in conjunction with measurements of steady-state photoconductivity, are consistent with the following scheme. The principal route for the formation of charge carriers is via the first excited singlet state, although the lowest triplet state can, t o some extent, contribute to charge - carrier production. The mobility of the carriers is low and is concentration-dependent, being lower at higher carrier concentration. The decay of the photocurrent is the result of a diffusion-limited bimolecular recombination, with a capture radius of approximately one molecular diameter. The experiments indicate that carriers produced thermally in the dark do not interact with light-produced carriers.

Organic solids exhibit a wide range of electrical and related properties. They occur as crystals, glasses, polymers and thin films; they may be insulators, semiconductors, conductors or superconductors; and they may show luminescence, nonlinear optical response, and complex dynamical behaviour. The book provides a broad survey of this area, written by international experts, one third being drawn from Eastern Europe. Electrical, optical, spectroscopic and structural aspects are all treated in a way that gives an excellent introduction to current themes in this highly interdisciplinary and practically important area. The coverage is especially strong in the areas where electrical and optical properties overlap, such as photoconductivity, electroluminescence, electroabsorption, electro-optics and photorefraction.

Organic solids exhibit a wide range of electrical and related properties. They occur as crystals, glasses, polymers and thin films; they may be insulators, semiconductors, conductors or superconductors; and they may show luminescence, nonlinear optical response, and complex dynamical behaviour. The book provides a broad survey of this area, written by international experts, one third being drawn from Eastern Europe. Electrical, optical, spectroscopic and structural aspects are all treated in a way that gives an excellent introduction to current themes in this highly interdisciplinary and practically important area. The coverage is especially strong in the areas where electrical and optical properties overlap, such as photoconductivity, electroluminescence, electroabsorption, electro-optics and photorefraction.