The book summarises contemporary knowledge about the theory of atomic and molecular clusters. New results are discussed on a high theoretical level. Access to this field of research is given by an explanation of the various subjects in introductory chapters.

The Second International Conference on Atomic and Nuclear Clusters '93 was orga nized in a joint effort by the 'Demokritos' National Center for Scientific Research, G. S. Anagnostatos (representing the atomic physics) and the Hahn-Meitner-Institut, W. von Oertzen (representing the nuclear physics). The subject of clusters - small aggregates of particles - is a topic of primary interest in both atomic and nuclear physics, and also in other fields like in the case of quark-structure of baryons and in cosmology. The interplay between atomic and nuclear physics is a particularly fascinating one because many concepts are common to both fields (quantal effects, shells, geometric structures, collective modes, fission etc. ) This conference was the second after the first one organized by Professor M. Brenner in Abo (Finland) in 1991. The general atmosphere of a joint forum for atomic and nuclear physicists was very fruitful and thus the decision to have a sequence of such meetings has been taken. A third one is planned in St. Petersburg (Russia) with Professor K. Gridnev (St. Petersburg) and Mme. Professor C. Bnkhignac (Orsay) as Chairpersons. The conference site, Fin\. on Santorini island (Greece), was a wonderful choice for a conference. It is small, which helps to keep people concentrated in a smaller community, it has a perfect convention center, the P. Nomikos Conference Center, and a very beautiful landscape formed by a large volcanic crater.

In these days of specialization it is important to bring together physicists working in diverse areas to exchange and share their ideas and excitement. This leads to cross-fertilization of ideas, and it enriches, as in biological systems, a specialized field with new strength, development and direction derived from another area. Although this might be an uncommon thing, it is an important step in our under standing of the physical world around us, which is, after aIl, the main purpose of physics. The seed for this conference was really sowed when one of us (MB) and Mr. Manngärd showed some a-scattering data at backward angles to FBM one summer about four years ago. That occasion led to a long research collaboration between the Abo Akademi physicists and other scientists in several countries. The actual idea to explore the possibility of holding a conference, however, crystallized in the summer of 1989 during a visit of FBM to Abo Akademi. The final decision to organize a conference was made after MB visited Profes sor Ben Mottelson in Copenhagen and Professor Anagnostatos in Athens. At this point it was recognized that there are similarities as weIl as differences between clustering phenomena in nuclei and systems consisting of atoms. It was therefore conjectured that it could be very stimulating to bring together these groups to exchange their ideas and to leam from each other's fields. A conference along these lines, we hoped, would contribute to an increased mutual understanding.

This book describes the experimental generation, detection, and interrogation of clusters. They are classified according to their bonding types, and theoretical models are presented which account for their respective properties. Examples are given of present and possible future applications in electronic, optical, and magnetic devices.

Atomic Clusters with Unusual Structure, Bonding and Reactivity: Theoretical Approaches, Computational Assessment and Applications reviews the latest computational tools and approaches available for accurately assessing the properties of a cluster, while also highlighting how such clusters can be adapted and utilized for the development of novel materials and applications. Sections provide an introduction to the computational methods used to obtain global minima for clusters and effectively analyze bonds, outline experimental approaches to produce clusters, discuss specific applications, and explore cluster reactivity and usage across a number of fields.Drawing on the knowledge of its expert editors and contributors, this book provides a detailed guide to ascertaining the stability, bonding and properties of atomic clusters. Atomic clusters, which exhibit unusual properties, offer huge potential as building blocks for new materials and novel applications, but understanding their properties, stability and bonding is essential in order to accurately understand, characterize and manipulate them for further use. Searching for the most stable geometry of a given cluster is difficult and becomes even more so for clusters of medium and large sizes, where the number of possible isomers sharply increase, hence this book provides a unique and comprehensive approach to the topic and available techniques and applications. - Introduces readers to the vast structural and bonding diversity that clusters show and reflects on their potential for novel application and material development - Highlights the latest computational methods and theoretical tools available for identification of the most stable isomers and accurate analysis of bonding in the clusters - Focuses on clusters which violate the rules established in traditional chemistry and exhibit unusual structure, bonding and reactivity

Clusters of Atoms and Molecules is devoted to theoretical concepts and experimental techniques important in the rapidly expanding field of cluster science. Cluster properties are dicussed for clusteres composed of alkali metals, semiconductors, transition metals, carbon, oxides and halides of alkali metals, rare gases, and neutral molecules. The book is composed of several well-integrated treatments all prepared by experts. Each contribution starts out as simple as possible and ends with the latest results so that the book can serve as a text for a course, an introduction into the field, or as a reference book for the expert.