Three series of metal-oxide cluster cations were produced by pulsed-laser ablation of YBa2Cu3O7=x high-temperature superconductive material in high vacuum. While Ba in the composite-oxide was replaced by other alkali-earth metal, such as Sr, Ca, Mg, the compositions of produced cluster ions were different. After analysis of the compositions of the cluster ions as well as their relative signal intensities, the interactions between the components of the metal-composite-oxide samples were studied
