title: Formation of the magic cluster Na8 in noble gas matrixes.
abstract: The sodium molecules Na(2), Na(4), and Na(8) 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 Na(4) 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.
authors.affiliation: Anorganische Chemie, Fachbereich Chemie der Universität Dortmund, Germany. kornath@chemie.uni-dortmund.de
authors.forename: Andreas
authors.initials: A
authors.lastname: Kornath
authors.forename: Anja
authors.initials: A
authors.lastname: Zoermer
authors.forename: Ralf
authors.initials: R
authors.lastname: Ludwig