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Abstract: The hydrogenation of endohedral X@B16N16 (X=Li+, Na+, K+, Mg2+, Ne, O2−, S2−, F−, and Cl−) complexes has been studied at the B3LYP/6-31G* level of density functional theory. The structures and properties of the most stable X@B16N16 and X@B16N16H32 complexes along with the size and charge of the endohedral species are discussed comprehensively from the aspects of the average B–N bond lengths, average binding energy per H2 molecule and inclusion energy. On the basis of computational results, it is found that the small and highly charged guest species is favorable for endohedral, and the average binding energies of hydrogenated X@B16N16 complexes are larger than that of B16N16 cage on the whole. Especially, Mg2+ encapsulation is favorable thermodynamically and it could obviously reduce the hydrogen adsorption barriers by 12.05kcal/mol. Also, the reaction of Mg2+@B16N16 +16H2 →Mg2+@B16N16H32 will reverse at 260K, which is higher than the reversing temperature 110K for the reaction of B16N16 +16H2 →B16N16H32. [Copyright &y& Elsevier]

Abstract: The equilibrium geometries, electronic states, vibrational frequencies and energies of (GaP) n and (GaP) n − (n =7–9) have been calculated by hybrid B3LYP and B3PW91 functionals at 6-31+G(d) level. The results reveal that the lowest lying electronic states’ geometries of the neutral have the same molecular symmetry as the corresponding anions’. (GaP)7 is shown to have a singlet ground state (1A1) with C 3v symmetry. (GaP)8 is found to be a closed-shell molecule with S 4 symmetry. (GaP)9 takes on a singlet ground state (1A′) with C 3v symmetry. The charge-induced structural changes in these clusters have been discussed. Moreover, natural bond orbital (NBO) analysis implemented to gain insight into the bonding pattern of these clusters indicates these clusters have a partial ionic character. Natural electron configuration shows the extra electron is mostly localized on the metal atoms. In addition, three types of energy separations reported in this work are the adiabatic electron affinity (AEA), the vertical detachment energy (VDE), and the vertical electron affinity (VEA). Herein, adiabatic electron affinities (AEAs) and vertical detachment energies (VDEs) for all of interest are excellent consistent with experiments, as strongly supports the optimized structures. And the order of AEAs and VDEs of the (GaP) n − are both (GaP)9 <(GaP)8 <(GaP)7. (GaP)9 exhibits the lowest adiabatic electron affinity of all the clusters studied, indicating a particularly stable neutral species. [Copyright &y& Elsevier]

Abstract: The geometries, stabilities, electronic and magnetic properties of Co13− n M n (n =1, 2, M=Mn, V and Al) clusters have been systematically studied by means of a density functional theory with generalized gradient approximation. The calculated results show that the most stable structures of Co12M and Co11M2 (M=Mn, V and Al) clusters all prefer icosahedral configurations with high symmetry, in which the Mn and Al atoms prefer to occupy surface positions of the icosahedron, while the V atom favors the central position. In these clusters, the Al atoms have nearly zero local magnetic moments, while Mn and V atoms are coupled with the remaining Co atoms ferromagnetically and antiferromagnetically, respectively. These several kinds of different magnetic behaviors result in the total magnetic moment enhancement with doped Mn and reduction with doped V/Al as compared to the optimal icosahedral structure of Co13 cluster, in good agreement with recent Stern–Gerlach experiment results . Analysis based on the binding energy and density of state has been made to clarify different magnetic behaviors of the Co12M and Co11M2 (M=Mn, V and Al) clusters. In addition, our calculations suggest that in the Stern–Gerlach molecular beam the Co12M and Co11M2 (M=Mn, V and Al) alloy clusters mainly exist as icosahedral structures. [Copyright &y& Elsevier]