Inverse photoemission from solids: Theoretical aspects and applications

The current status of inverse photoemission from clean crystals is reviewed with special emphasis on theoretical aspects and applications. The article focuses on general photoemission theory, the effective barrier potential at metal surfaces and the calculation of inverse photoemission spectra for both bulk and surface electronic states. In particular the information originating from inverse photoemission on Shockley and image-potential surface states, effective masses of mage-potential states and spin-split surface states at ferromagnets is discussed.