A theoretical study on the structures of phosphorus clusters P-12

Twenty-eight structures of P-12 were acquired with molecular graphics and o ptimizations were carried out with molecular mechanics, PM3 semi-empirical and ab initio calculations. In these structures, the phosphorus atoms could be two-fold, three- fold, four-fold coordinated. The model of D3d symmetry derived from condensing two cuneane P-8 via the sharing of four atoms is t he most stable isomer. The imaging of enough cluster models can help to loc ate the global minimum. Many P-12 structures are characterized by atoms in three-fold mode and those that have atoms(s) in two-fold coordination have high energies. Both tetrahedral P-4 and cuneane P-8 are common components a nd could be important candidates for the construction of larger clusters. A planar pentagonal structure is more popular than a hexagonal one in phosph orus clusters.