Induced super-halogen behavior of metal moieties in halogen-doped clusters: LinI(-) and AlnI(-), n = 13, 1, 2, 3.
A comparative density functional theory (DFT) study of a series of neutral and negative-ionic lithium and aluminum clusters doped with iodine atom is presented. The I atom is found to preserve the same position at Li13 with and without the negative charge and Li13 to vary its shape from prolate to oblate with changing spin state of Li13I. Both the Mulliken and natural charges are considered, the natural-charge separation between the metal and halogen moieties being generally much larger (except for Al13I-). In LinI-, the additional electron is strongly localized on the metal moiety starting from n = 1, even though the electron affinity of Lin is much smaller than that of I. Such a super-halogen behavior of Lin is induced by highly electronegative iodine making the two components charged in LinI and leading to a charge-dipole interaction with the additional electron. In AlnI-, similar factors result in Aln being more negative than I already for n = 3, even though the electron affinity of I is higher, the effect escalating for n = 13.
Leung
Hobart
H
Faculty of Science, University of Ontario Institute of Technology, Oshawa, Ontario L1H 7K4, Canada.
Naumkin
Fedor Y
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