Photoabsorption resonances of Na(20), Na(21)Cl and Na(22)Cl(2) clusters

Plasma resonance profiles in the visible part. of the spectrum were measured by photoabsorption spectroscopy for the clusters Na(20), Na(21)Cl and Na(22)Cl(2) in a beam. The resonance positions in Na(20) and Na(21)Cl are close, suggesting that the Cl(-) ion does not; locate at the center of the metallic droplet and does not strongly modify the effective valence electron density. The spectrum of Na(22)Cl(2) is noticeably dissimilar to the other two, raising the possibility of structural differences and/or incomplete charge transfer.