Quote:This book explains the phenomena, reviews the best materials, and presents the most relevant applications. The behaviour of electrons in atoms, liquids, solids, and periodic crystals is described, and the possibilities of new artificial materials are discussed. In themselves, electrons are intriguing, sometimes displaying particle-type and other times wave-type behaviour. Full understanding of wave properties requires quantum mechanics, often seen as a barrier due to the unfamiliarity of the concepts involved and the complexity of the mathematical apparatus needed. A key aim is to overcome these difficulties. Underpinning theory is explained as simply as possible.