On the Structure of Boat-Shaped Hexalead(II) Cations with OH Bridges

Abstract

Using Hartree-Fock, B3LYP, and MP2 treatments, the optimal boat-shaped geometries and corresponding electronic structures of [Pb6Om(μ3-OH)n]q complex cations with total charges q = 12 - 2m - n, m = 0 or 1, n = 6 or 8, are investigated. Whereas the [Pb6(μ3-OH)6]6+ cation is unstable, the remaining structures preserve C2v symmetry. Direct Pb-Pb interactions are weakly antibonding in all the systems under study. The clusters are held together exclusively by relatively weak Pb-O bonds. The effects of central O and two additional μ3-OH bridges in [Pb6O(μ3-OH)8]2+ are not fully cooperative. [Pb6O(μ3-OH)6]4+ and [Pb6(μ3-OH)8]4+ may coexist in water solutions in comparable concentrations.