FORMATION OF SODIUM-HYDROXIDE IN MULTIPLE SODIUM-WATER CLUSTER COLLISIONS

In a pickup arrangement, the reactive scattering of sodium atoms and d imers with water clusters (H2O)(m), m less than or equal to 140, is in vestigated. The water cluster beam is generated in a pure supersonic e xpansion and crosses an atmosphere of sodium vapor. The reaction produ ces are detected by photoionization at a wavelength of 360 nm (3.45 eV ) and mass analyzed in a reflectron time-of-flight mass spectrometer. Doping the H2O clusters with Na atoms results in the formation of solv ated sodium atoms Na(H2O)(m), representing the distribution of the pur e water clusters. At higher sodium pressures also Na-2 dimers an produ ced, which then react in a second step with the solvated Na atoms to p roducts of the type Na(NaOH)(2)(H2O)(m) and, to a lesser extent, also to Na(NaOH)(4)(H2O)(m). The size range follows that of the precursors with a pronounced maximum of intensities between m = 6 and 14 in the f ormer case.