Actinide coordination chemistry – a unique example of a homoleptic complex of nine-coordinate thorium(IV)

The dimethylsulfoxide (dmso) solvate of Th(IV) perchlorate is readily obtained from acidic aqueous Th(IV) solutions and has a formulation established from a single crystal structure determination of [Th(dmso-O)9](ClO4)4 · 4dmso; triclinic, , a=12.4811(8) Å, b=12.4879(8) Å, c=23.969(2) Å, α=94.684(1)°, β=95.823(1)°, γ=119.347(1)°. The primary coordination sphere of the Th is of tricapped trigonal prismatic form, with the symmetry of the [Th(dmso-O)9] entity being close to C3h.