Nanocluster Growth and Coalescence Modulated by Ligands

We describe a model of nanocluster formation that incorporates competition between ligand adsorption and nanocluster growth. Growth occurs through the addition of a metal-ligand complex and coalescence of nanoclusters. The competition between ligands for binding sites on the nanoclusters and growth of the nanoclusters through coalescence creates interesting growth pathways. The patterns are reminiscent of those observed in the synthesis of gold thiolate nanoclusters. For a particular set of rate coefficients, described herein, we observe the formation of a kinetically stable nanocluster that participates in coalescent growth. This determines the size interval of the resulting nanoclusters in the size distribution. The kinetically stable cluster can be tuned by modifying the functional form of the number of surface sites on the nanoclusters, thereby changing the growth pathway and the final sizes of the clusters.