Structure and Stability of the LiXe and LiXe Clusters.

We have studied the structure and stability of the ionic LiXe and neutral LiXe (n = 1-35) small clusters. The potential energy surface of the ionic cluster is described using additive potentials, which represent the pair interactions taken from the best available coupled cluster ab initio calculations. The V and V potentials have been fitted by Tang and Toennies and Lennard-Jones (LJ) forms, respectively. The structure of LiXe neutral clusters have been investigated using a model potential and ab initio calculations. We have used the LiXe potential in its ground state and fitted to the Tang and Toennies formula. The LiXe optimized geometry is, then, used for one electron self consistent filed calculation of the only alkali valence electron interacting with the LiXe cluster. In order to determine the geometry of LiXe and LiXe clusters and their isomers, the potential energy surface has been explored by the Monte Carlo basin Hopping method. Their relative stability was studied by evaluating the energy and the energy differences as function of number n of Xenon atoms in clusters. It was shown, for LiXe, that n = 4, 6, 10, 14, 16, 18, 20, 22, 24, 26, 28 and 30 are the most stable structures. [ABSTRACT FROM AUTHOR]