September 25h -Friday- 12:10
"ANALYZING AND DETERMINING THE PROPERTIES OF NANOPARTICLES"
Michael Springborg(Physical and Theoretical Chemistry University of Saarland. Germany)
One of the big challenges facing theoretical studies of nanoparticles is to determine the structure of the global total-energy minimum. During the last couple of decades, more different approaches have been proposed for tackling this problem and also applied to various systems in combination with more or less accurate descriptions of the total energy as a function of structure. As result of such calculations, one obtains, first of all, the nuclear coordinates and the total energies as functions of the size of the clusters. Another challenge is then to extract chemically or physically relevant information from this often very large amount of information. In this presentation, we shall give examples from our own work on the unbiased determination of the structure of different types of clusters. We have used different structure-optimization methods as well as approximate total-energy methods and shall put special emphasis on the analysis of the results. This includes the identification of particularly stable clusters as well as the structural shape and similarity with various types of reference structures. As examples, we shall consider isolated metal clusters and metal clusters deposited or grown on metal surfaces. Also semiconductor clusters with one or more types of atoms shall be treated.
Facultad de CienciasSeminario departamento de Física Teórica Universidad de Zaragoza