The Theory Study For The Structures And Properties Of Pt_n N^0,±(n=1-5) Clusters

We know that the cluster is a basic constitutional unit of nanomaterials whose properties could be designed by controling compositions,geometry structures and the size, Therefore,it is an important step to study the ground state structures,stablility and electronic properties of the cluster for designing micro structures of a new nanomaterial with prescribed properties. In this article, Gaussian03 program based on density functional theory is applied. The geometric structures of PtnN^0,± (n=1-5) are all optimized systematically, and the the ground state structures or the stable structures are investigated. The main results are as follows:At first,the geometric structures of PtnN^0,±(n=1-5) clusters are optimized by the B3LYP/LANL2DZ method of density function theory, then, the ground state structures are obtained by comparing the energies of the isomers at different size. The results show: the average binding energies of the PtnN^0,± (n=1-5)clusters, for neuter and cationic clusters, with the increase of atoms number, the average binding energies are gradual growth, it shows: Thermodynamics stability is better. For anion clusters, the average binding energies of the Pt2NˉandPt3N-are the maximum, it shows: Thermodynamics stability is the best. ForΔ2 E,ΔE (n), the chemical activity of Pt2N0,±clusters is the weak, the chemical stability of Pt2N0,±clusters is the strongest. The value of enthalpy shows that the reaction is the exothermic reaction.For the energy gap, the chemical activity of PtN cluster is the strongest, the chemical stability of PtNˉcluster is the strongest.Secondly,the spectral properties and electronic structure of PtnN^0,±(n=1-5) clusters, ground state structures are studied, The results show: the number of the vibration peak of the Pt5N0,±clusters are the most in all the IR and Raman spectrums, the intensity of the vibration peak of the Pt2Nˉcluster is the highest in all the IR spectrums, the intensity of the vibration peak of the Pt3Nˉcluster is the highest in all the Raman spectrums; the magnetic moment of the Pt2Nˉ,Pt3N±and Pt4N±clusters is quenched;the aromaticity is found in Pt2N,Pt2Nˉand PtnN^0,±(n=4,5)clusters, the aromaticity of the Pt4N,Pt5N0,+ is relatively strong; the N atoms gain the charge when the clusters are formed, but some Pt atoms gain the charge and other Pt atoms lose the charge; for the average of polarizability tensor, the bond interaction of the neuter and cationic clusters present a rising tendency with the number of n, the bond interaction of the Pt4Nˉin anion clusters is the strongest.Above all, it is the first time to study the physical and chemical properties of the ground states of PtnN^0,±(n=1-5) clusters, All of these clusters research will play an important role in finding new functional materials.