Stoichiometric and ultra-stable nanoparticles of II-VI compound semiconductors

Nanoparticles of (CdSe)(n) are found extremely stable at n = 33 and 34 with structures distinctively different from the bulk fragments. They grow exclusively in large amount with a simple solution method. The diameter is determined as 1.5 nm. Such ultra-stable nanoparticles had been predicted both theoretically and experimentally after the discovery of carbon fullerenes, but not been produced macroscopically in any other element or compound system. First-principles calculations predict that the structures of (CdSe)(33) and (CdSe)(34) are puckered (CdSe)(28)-cages accommodating respectively (CdSe)(5) an (CdSe)(6) inside to form a three-dimensional network of essentially hetero-polar sp(3)-bonding.