A reissue of a classic Oxford text. The book sets out theoretical concepts and makes comparisons with experiments for a wide variety of phenomena in non-crystalline materials.

This second edition deals in an elementary way with electrons in non-crystalline systems. It reflects advances in the theory of interactions in non-crystalline systems, provides a more detailed discussion of the "minimum metallic conductivity", and addresses the relevance of disorder in the new high-temperature semiconductors.

The first advanced textbook to provide a useful introduction in a brief, coherent and comprehensive way, with a focus on the fundamentals. After having read this book, students will be prepared to understand any of the many multi-authored books available in this field that discuss a particular aspect in more detail, and should also benefit from any of the textbooks in photochemistry or spectroscopy that concentrate on a particular mechanism. Based on a successful and well-proven lecture course given by one of the authors for many years, the book is clearly structured into four sections: electronic structure of organic semiconductors, charged and excited states in organic semiconductors, electronic and optical properties of organic semiconductors, and fundamentals of organic semiconductor devices.