Ab InitioPhotoabsorption Spectra and Structures of Small Semiconductor and Metal Clusters

We have detected an error on the given values of the static polarizability per atom of Si clusters.The correct averaged values are 5.0, 4.7, 4.3, and 4.4 Å 3 for Si 4 ͑D 2h ͒, Si 4 ͑T d ͒, Si 6 ͑D 4h ͒, and Si 6 ͑C 2y ͒, respectively.These changes do not alter any of the conclusions in the Letter.