Formation of Ca+ (EtOH)(m) from alcohol solutions of CaCl2

A continuous liquid flow of a calcium chloride (CaCl2) solution in ethanol (EtOH) in a vacuum (a liquid beam) was irradiated with a 266 nm laser, and ions ejected from the surface following multiphoton ionization via the CTTS (charge transfer to solvent) band of Cl- were observed by a time-of-flight mass spectrometer. A variety of core ions (Ca+, CaOEt+, CaOH+, CaCl+, Hi, etc.) are formed by reactions involving Ca2+, solvated electrons, and solve nt molecules after the CTTS excitation by the laser irradiation and are eje cted into vacuum with several accompanying alcohol molecules. The proposed mechanism is verified by the change of the ion intensity with introduction of an electron scavenger, CHCl3, in the solution. The cluster ion, Ca+(EtOH )(m), remains intact for m < 3, while it dissociates into CaOEt+(EtOH)(m-1) for m greater than or equal to 3. This size-dependent dissociation is simp ly explained by the energetics.