Cationic clusters lowest-energy structure

Tables 6 and 7 summarise the calculations carried out on alkali metal clusters with 2 to 8 valence electrons reported in the papers of Fantucci et al. The tables contain the point group (and spin multiplicity), moments of inertia, L parameter, and, where available, the energy separation (AE) between that structure and the lowest energy structure for that stoichiometry. The structures include those of neutral, cationic and anionic clusters of lithium and sodium.

The structures of Si clusters derived from various optimizations ( 3) were vetted by comparisons with experiments ( 2). Table 1 presents calculated and measured mobilities for lowest-energy Sin cations and anions. 

The smaller cluster ions 83", 84" and 85 + have been examined by Zakrzewski and von Niessen at the HF/6-3H-G level [82]. The lowest cationic states are predicted to be 82, and A" for 83 (Cyv), 84 (I>4h) and (Cs), respectively. The ionisation processes may result in significant structural relaxation leading to the sequence of states different from that of the vertical states. The calculated lowest adiabatic ionisation energies, using the GI method with a very large ANO basis set, are 9.53, 8.05, and 8.20 eV for 83, 84 and 85 , respectively. 

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