Reactivity and stability of bimetallic clusters

Using two independent vaporization lasers, bimetallic clusters composed of transition elements and A1 were generated by the laser vaporization method. Reactivity toward hydrogen adsorption of bimetallic clusters was compared with genuine clusters. It was found that A1 which has no reactivity toward hydrogen plays a role of either inhibitor or accelerator of the reaction when A1 is mixed with Nb or Co. Unusual stability of Co₁₂ V₁ in contrast to the high reactivity of Co_12–13 is attributed to the rigid geometric structure where V occupies the central position.