The Structure And Stability Research On Tisbnsmall Clusters Based On The First Principle Theory

Cluster is widespread in nature and human practice. On the research of clusters,not only on the atomic and molecular physics and condensed matter physics has far-reaching significance, but also will promote theoretical physics, computationalphysics and quantum mechanics.The research of structure and stability of clusters is a begginning of atomicphysics and basis to study the change rule of bigger clusters and solid. Today, fromexperiment we can not survey the fundamental structure of clusters,including threeatom or more.So it is important to get it by theory and calculation.In this paper, the structures of diatomic molecules TiX（X=N, P, As, Sb,Bi）are calculated and research using of Gaussian03program, which is one ofquantum mechanics methods. And the use of Murrell-Sorbie analytic functionfitting a potential energy function, and spectral parameters and calculate the forceconstant. Calculation of the molecular system through the bond length, frequency,energy, come to the binding energy of molecular system, ionization energy, electronaffinity and to further study the stability of the molecule and the chemical activity.The results show that the molecular structure of TiN is the most stable, the chemicalactivity of TiP is the weakest, and TiN is more stronger. Consider to TiSb_n clusterin the field of practical applications has been a certain application, and less at homeand abroad of their research.Therefore, we carried out a systematic theoretical studyon TiSb_n （n=1~6） clusters. Calculated the stable structure of clusters,Identified the ground state structure,the average binding energy and the second-order differential of the clusters. The results show that the TiSb5the stability of thestrongest.