The crystal structure at STP of this metal is by far the most complex of all metallic elements, with 58 atoms per unit cell. A dark green liquid oxide of this metal explodes on contact with most organic compounds. Bleach oxidizes this metal from 3+ to 5+ in a reaction catalyzed by a complex of this metal with a salen ligand, the Jacobsen epoxidation. (-5[1])In one cluster, four atoms of this metal are successively oxidized through states S0 to S4 to then oxidize (*) water. This metal’s dioxide is the most common cathode for alkaline batteries. A brown precipitate of this metal’s dioxide in Baeyer’s test indicates the presence of alkenes or alkynes, which an oxyanion of this metal converts to diols. For 10 points, name this transition metal that has the 7+ oxidation state in (10[1])an oxyanion that is a powerful oxidizer with a magenta color. ■END■ (10[1]0[1])