Small magnesium clusters: between van der waals and valence bonds.

The magnesium molecules Mg(2), Mg(3), Mg(4), and Mg(5) have been isolated in rare-gas matrixes at 8 K and characterized for the first time by Raman spectroscopy. The vibrational frequencies were compared with those obtained by density functional theory calculations. The fundamental frequency of the dimer was observed at 97 cm(-1) (Ar matrix), and a bond length of d(Mg-Mg) = 340.

A combined matrix isolation and ab initio study of bromine oxides.

Bromine oxides have been generated by passing a mixture of Br(2)/O(2)/Ar through a microwave discharge. The products were stabilized at 6.5 K in an excess amount of argon.

Formation of the magic cluster Na8 in noble gas matrixes.

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.

Raman Spectroscopic Investigation of Matrix Isolated Rubidium and Cesium Molecules: Rb(2), Rb(3), Cs(2), and Cs(3)(,)(1).

The rubidium molecules Rb(2) and Rb(3) and the cesium molecules Cs(2) and Cs(3) were isolated in argon matrixes and characterized for the first time by Raman spectroscopy. The fundamental frequencies of the dimers were observed at 59.1 cm(-)(1) for the rubidium dimer and 45.

Small Potassium Clusters.

The molecules K , K , and K (structure shown on the right) have been isolated in krypton matrices at 15 K and characterized by Raman spectroscopy. Comparison of the experimental data with density functional calculations supports the prediction that potassium clusters are not only bonded by the valence electrons, but that there is also a contribution from the core electrons.