physical and chemical properties of cluster systems at the sub-nano and nano-scale are often found to differ from those of the bulk material, instead displaying a unique dependence on size, geometry and composition. This realm of cluster science “where each atom counts” has undergone an explosive growth in activity during the last two decades, largely due to the exciting prospects of using clusters as building blocks for new materials. Innovations in both experimental methods and theoretical techniques available for studying their behavior have been crucial in stimulating new activities emerging in this rapidly moving field. On the experimental side, the developments in supersonic beams, molecular jets, and other techniques now allow synthesis, characterization, and investigation of the properties of selected clusters of any size and composition.On the theoretical side, developments in theoretical methods aided by the progress in computational resources now permit investigations of large clusters, bringing theory to the size regimes investigated in many diverse experiments. This has enabled new insights to be gained into the experimental observations; providing structural and other information that is difficult to access experimentally, and often guiding the experimental effort. This experiment-theory synergistic effort is laying the foundation for creating new materials using atomic or compound clusters of selected electronic properties and geometries. Findings from our recent work show that clusters can function as superatoms, thereby mimicking selected elements of the periodic table. If this concept is found to be broadly applicable, it would offer the exciting prospect of using clusters as building blocks to achieve a level of atomic control in the design of materials with desirable collective traits. The enormous impact that would arise from the ability to design materials with chosen properties is well recognized, and the prospects of new technological developments likely to arise from innovative achievements in the area of nanoscale science is boundless. A major effort of work is directed towards the electronic structure, geometry and the magnetism of clusters. The theoretical schemes use first-principles density functional methods capable of describing clusters having up to 100 atoms. We have already studied neutral and charged clusters of many elements and have provided information on their geometries and electronic structure. Our current work is focusing on multiple atom clusters, such as doped Zinc Oxide clusters, Silicon Oxide clusters and metal doped Silicon clusters. We are investigating how these various clusters are formed, how they grow, and how their properties can be modified by adding foreign atoms. Other projects of interest follow.
Superatoms
One of the most significant results we have found is the presence of the Al13- and Al142+ superatoms whose behaviour mimics that of Halogens and Alkaline Earth atom respectively. More recently Al7- whose behaviour mimics that of Halogens and was found to show multiple valence with both 18 and 20 valence electrons.
Cluster Assembly
The holy grail of cluster science is the formation of cluster assembled materials. We are interested in the behavior and properties of of Zintl phases and their parent clusters as well as finding ligands and countercations which stabilize clusters.
Magnetic Properties
We are also interested in the magnetic properties of clusters including transition metal doped zinc oxide clusters, Iron Oxide, Manganes Oxide and other transition metal clusters.
