density functional;
systematic trend;
cobalt-doped carbon cluster;
ionization potential;
electron affinity;
D O I:
10.1016/j.ijms.2008.02.003
中图分类号:
O64 [物理化学(理论化学)、化学物理学];
O56 [分子物理学、原子物理学];
学科分类号:
070203 ;
070304 ;
081704 ;
1406 ;
摘要:
The structure and properties of the different linear, fan and cyclic isomers of CoCn+ and COCn- (n = 1-8) clusters have been calculated using the B3LYP method with the 6-311+G(d) basis set. The stability of clusters as a function of the size has been discussed in terms of the incremental binding energies. Linear, fan and cyclic structures of CoCn+ clusters show a clear even-odd alternation in stability, n-odd members being more stable than the corresponding n-even ones. An opposite parity effect is found for linear and fan CoCn+ clusters, whereas the relative stability of cyclic isomers decrease with n. Linear structures are the most stable CoCn+ and COCn- clusters, with the only exception Of COCn+/- and COC7- where the fan and cyclic. arrangements are slightly lower in energy. The computed ionization potentials for the three structures show a clear even-odd alternation, with higher values for n-even clusters than for n-odd ones. Electron affinities for CoCn clusters increase along the series. (c) 2008 Elsevier B.V. All rights reserved.