Formation of platinum and palladium clusters with carbonyl phosphine ligands
a general method available for the synthesis of carbonyl phosphine clusters of Palladium and Platinum has b een found. Structural principles of cluster framework formation are discussed. The most simple building blocks for metal poly- hedra are triangle and butterfly and their combination "Tiare'! This construction principle can be applied for results inter- pretation and for the directional synthesis of new clusters. Metal clusters in the size range up to a hundred atoms are at present one of the most interesting frontiers of the coordination chemistry. The large clu- sters are of greater interest in view of both the structure and bonding in their metal core and the fact t hat they may model ligand coordination on me- tal surfaces. There is a general method available for the s ynthesis of large and giant c lusters: the reduction of noble metal salts by various r eduction agents in the presence of ligands which can block the surface of growing particles and prevent their aggregation. The problem of interest is also the mechanism of cluster enlargement in solutions. The most simple concept states that enlargement of clusters proceeds through atom b y a tom addition. This process can be modeled as follows: