On the structure of boat-shaped hexalead(II) cations with OH bridges

摘要

Using Hartree - Fock, B3LYP, and MP2 treatments, the optimal boat-shaped geometries and corresponding electronic structures of [Pb6Om(mu(3)-OH)(n)](q) complex cations with total charges q = 12 - 2m - n, m = 0 or 1, n = 6 or 8, are investigated. Whereas the [Pb-6(mu(3)-OH)(6)](6+) cation is unstable, the remaining structures preserve C-2v 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 mu(3)-OH bridges in [Pb6O(mu(3)-OH)(8)](2+) are not fully cooperative. [Pb6O(mu(3)-OH)(6)](4+) and [Pb-6(mu(3)-OH)(8)](4+) may coexist in water solutions in comparable concentrations.