This paper studies the equilibrium geometries and electronic properties of Ben and BenLi clusters, up to n=15, by using density-functional theory（DFT） at B3LYP/6-31G（d） level. The lowest-energy structures of Ben a...This paper studies the equilibrium geometries and electronic properties of Ben and BenLi clusters, up to n=15, by using density-functional theory（DFT） at B3LYP/6-31G（d） level. The lowest-energy structures of Ben and BenLi clusters were determined. The results indicate that a single lithium impurity enhances the stability and chemical reactivity of the beryllium clusters. It finds that the geometries of the host clusters change significantly after the addition of the lithium atom for n ≥8. The lithium impurity prefers to be on the periphery of beryllium clusters, and occupies vertex sites. Both Be4Li, Be9Li, and Be13Li were found to be particularly stable with higher average binding energy, local peaks of second-order energy difference and fragmentation energies. For all the BenLi clusters studied, we found charge transfers from the Li to Be site and co-existence of covalent and metallic bonding characteristics.展开更多
This paper studies a new conserved quantity which can be called generalized Mei conserved quantity and directly deduced by Mei symmetry of Birkhoff system. The conditions under which the Mei symmetry can directly lead...This paper studies a new conserved quantity which can be called generalized Mei conserved quantity and directly deduced by Mei symmetry of Birkhoff system. The conditions under which the Mei symmetry can directly lead to generalized Mei conserved quantity and the form of generalized Mei conserved quantity are given. An example is given to illustrate the application of the results.展开更多
The structures and properties of Wn （n = 2-14） clusters were studied by using the density functional theory （DFT） at LSDA level. The most stable structures of Wn （n = 2-14） clusters with global minimum were dete...The structures and properties of Wn （n = 2-14） clusters were studied by using the density functional theory （DFT） at LSDA level. The most stable structures of Wn （n = 2-14） clusters with global minimum were determined. The average binding energy （Eb）, the first and second difference of total energy （△E, △2E）, the vertical detachment energy （VDE）, and the HOMO-LUMO gap versus the size were also discussed. The abrupt decrease of VDE and HOMO-LUMO gap at size n = 8 and 10 implied that tungsten clusters of W8 and W10 appeared to have metallic features. These changes were also accompanied by the delocalization of electron charge density and the strong hybridization between 5d and 6s orbits in W8 and W10 clusters. Our results are in good agreement with the available experimental data.展开更多
基金Project supported by the Xinjiang Normal University Excellent Young Teachers’ Foundation, China (Grant No XJNU0730)Xinjiang Normal University Priority Developing Disciplines’ Foundation
文摘This paper studies the equilibrium geometries and electronic properties of Ben and BenLi clusters, up to n=15, by using density-functional theory（DFT） at B3LYP/6-31G（d） level. The lowest-energy structures of Ben and BenLi clusters were determined. The results indicate that a single lithium impurity enhances the stability and chemical reactivity of the beryllium clusters. It finds that the geometries of the host clusters change significantly after the addition of the lithium atom for n ≥8. The lithium impurity prefers to be on the periphery of beryllium clusters, and occupies vertex sites. Both Be4Li, Be9Li, and Be13Li were found to be particularly stable with higher average binding energy, local peaks of second-order energy difference and fragmentation energies. For all the BenLi clusters studied, we found charge transfers from the Li to Be site and co-existence of covalent and metallic bonding characteristics.
基金Project supported by the Scientific Research Fund for Outstanding Young Teachers (Grant No XJNU0817)Fund for Prior Development Subject of Xinjiang Normal University and National Natural Science Foundation of China (Grant No 10864007)
文摘This paper studies a new conserved quantity which can be called generalized Mei conserved quantity and directly deduced by Mei symmetry of Birkhoff system. The conditions under which the Mei symmetry can directly lead to generalized Mei conserved quantity and the form of generalized Mei conserved quantity are given. An example is given to illustrate the application of the results.
基金Project supported by the Excellent Young Teachers’ Foundation of Xinjiang Normal University (Grant No XJNU0730)the Prior Developing Subject’ Foundation of Xinjiang Normal University
文摘The structures and properties of Wn （n = 2-14） clusters were studied by using the density functional theory （DFT） at LSDA level. The most stable structures of Wn （n = 2-14） clusters with global minimum were determined. The average binding energy （Eb）, the first and second difference of total energy （△E, △2E）, the vertical detachment energy （VDE）, and the HOMO-LUMO gap versus the size were also discussed. The abrupt decrease of VDE and HOMO-LUMO gap at size n = 8 and 10 implied that tungsten clusters of W8 and W10 appeared to have metallic features. These changes were also accompanied by the delocalization of electron charge density and the strong hybridization between 5d and 6s orbits in W8 and W10 clusters. Our results are in good agreement with the available experimental data.
