[Back]

A. Kornath, R. Ludwig, A. Zoermer:
"Formation of the Magic Cluster Na₈ in Noble Gas Matrixes";
Inorganic Chemistry, 41 (2002), 6206 - 6210.

The sodium molecules Na₂, Na₄, and Na₈ have been isolated in argon matrixes at 15 K and characterized for the first time by Raman spectroscopy. The vibrational frequencies are compared with density functional (DFT) calculations. The Na₄ cluster possesses a rhombic structure (D_2h) with calculated d(Na-Na) = 307.2 and 347.4 pm, respectively. For octasodium, a hypertetrahedral structure (T_d) is predicted in which each side of an inner tetrahedron with d(Na-Na) = 331.5 pm is capped by sodium atoms with a distance of d(Na-Na) = 348.7 pm. The green octasodium cluster is the first example of a matrix-isolated magic number cluster. Its formation from blue tetrasodium is discussed on the basis of the observed sequence of cluster growth.

http://pubs.acs.org/journals/inocaj/article.cgi/inocaj/2002/41/i24/pdf/ic011161m.pdf