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Theoretical study of stepwise chlorinated aluminide clusters Al13Cl n - (n = 1–9)статья
- Авторы: Kochnev V.K., Charkin O.P., Klimenko N.M.
- Журнал: Russian Journal of Inorganic Chemistry
- Том: 53
- Номер: 8
- Год издания: 2008
- Издательство: Maik Nauka/Interperiodica Publishing
- Местоположение издательства: Russian Federation
- Первая страница: 1263
- Последняя страница: 1273
- DOI: 10.1134/s0036023608080196
- Аннотация: The electronic and geometric structures, energy stabilities, normal mode frequencies, and spin density distributions (in radicals) of different stepwise-chlorinated aluminum clusters Al13Cl −n (n = 1–9) are calculated within the B3LYP approximation of the density functional theory using 6-31G* and 6-311+G* basis sets. The results are compared with analogous computation data on hydrides Al13H −n (n = 1–12) obtained at the same level. The general qualitative pattern for related series of hydrides, chlorides, and iodides (as well as fluorides and bromides) turns out to be similar in many respects. For all Al13X −n clusters with different electronegative substituents X, there is a set of a considerable number of low-lying closely spaced inner isomers (with a centered icosahedral cage), marquee isomers, and outer isomers (capped). The effects found by calculations in centered icosahedral isomers—localization of spin density on the trans-Al* atom in radical anions and its associated trans addition rule for an even substituent and the zigzag (odd-even) dependence of the energies D n (X) of successive addition of substituents X to the metal cage on n described in the framework of the molecular model of the valence states of the Al −13 superatom—should also be shared by many Al13X −n series with different X’s. The differences between hydrides Al13H −n and chlorides Al13Cl −n of the same type are quantitative. For the hydrides, inner isomers are preferable in the first half of the series (n = 1–6); and in the second half (n = 7–12), outer isomers are more favorable. For the chlorides, icosahedral isomers are preferable only at the very beginning of the series. In the other cases, nonicosahedral structures are most favorable, for which the situation becomes very complicated due to the large number of position isomers and the aforementioned simple rules found for centered icosahedral structures are fulfilled to a considerably less extent or not at all.
- Добавил в систему: Чаркин Олег Петрович