This series of books, which is published at the rate of about one per year, addresses fundamental problems in materials science. The contents cover a broad range of topics from small clusters of atoms to engineering materials and involve chemistry, physics, and engineering, with length scales ranging from Ångstroms up to millimeters. The emphasis is on basic science rather than on applications. Each book focuses on a single area of current interest and brings together leading experts to give an up-to-date discussion of their work and the work of others. Each article contains enough references that the interested reader can access the relevant literature. Thanks are given to the Center for Fundamental Materials Research at Michigan State University for supporting this series. M. F. Thorpe, Series Editor E-mail: thorpe@pa. msu. edu v PREFACE th th During the period 4 -8 August 1996, a conference with the same title as this book was held in Traverse City, Michigan. That conference was organized as a sequel to an interesting and successful WEM workshop in a similar area run by Profs. Hans Bonzel and Bill Mullins in May 1995. This book contains papers presented at the Traverse City conference. The book focuses on: atomic processes, step structure and dynamics; and their effect on surface and interface structures and on the relaxation kinetics of larger leng- scale nonequilibrium morphologies.

During the last decade, surface research has clearly shifted its interest from the macroscopic to the microscopic scale; a wealth of novel experimental techniques and theoretical methods have been applied and developed successfully. The Topics volume at hand gives an account of this tendency. For the understanding of surface phenomena and their exploitation in tech nical applications, the theoretical and experimental analysis at the microscopic level is of particular interest. In heterogeneous catalysis, for example, a chemical reaction takes place at the interface of two phases, and the process occurring at the surface is composed of a sequence of individual microscopic steps. These individual steps include adsorption, desorption, surface diffusion, and reaction on the surface. These elementary steps are greatly influenced by the structure and the dynamics of the surface region. Especially the catalytic activity may strongly depend on the structure of the catalyst's surface. The necessity of per forming surface investigations on a microscopic scale is also reflected clearly in research work relating to metal-semiconductor interfaces which determine es sentially the properties of electronic device materials. The experimental probe on the atomic scale, coupled with parallel theoretical calculations, showed that the electronic properties of a metal-semiconductor interface strongly depend on the crystallographic structure of the semiconductor; in particular, it is im portant to know in this context the modification of the atomic arrangement in the surface region caused by the termination of the crystal by the surface.

In den Oberflächen- und Nanowissenschaften ist ein fundiertes Verständnis lokaler Geometrie und Symmetrie von Kristallen und deren Oberflächen von entscheidender Bedeutung, da die Kristallstruktur viele physikalische und chemische Parameter mitbestimmt. Studenten und Forscher in Physik, Chemie und Materialwissenschaften erhalten hierzu mit dem vorliegenden Buch sowohl eine wertvolle Einführung wie auch ein nützliches Nachschlagewerk. Das Buch führt insbesondere scheinbar disparate Beschreibungen und Notationen zusammen, die ständig von Oberflächen- und Nanowissenschaftlern benötigt werden. Professor Hermann ist als Wissenschaftler im Bereich der theoretischen Oberflächenphysik ausgewiesen und bekannt als Koautor der NIST Surface Structure Database (SSD), einer absoluten Referenz in der Struktur- und Oberflächenwissenschaft. Seine Arbeiten zur Oberflächenvisualisierung dokumentiert er auch in diesem Buch, in dem aufwändige Grafiken der zahlreichen Beispiele die mathematisch formal gewählte Herangehensweise illustrieren. Übungen mit unterschiedlichem Schwierigkeitsgrad - von einfachen Fragen bis zu kleinen Forschungsprojekten - regen die Diskussion zu den unterschiedlichen Themen an.