Transformation of Mononuclear Plutonium(III) Tetrazolate Complexes into Dinuclear Complexes in the Solid State.

The salt metathesis reaction of Na(pmtz)·H 2 O [pmtz - = 5-(pyrimidyl)tetrazolate] and PuBr 3 · n H 2 O in an aqueous media leads to the formation of the mononuclear compound [Pu(pmtz) 3 (H 2 O) 3 ]·(3 + n ) H 2 O ( Pu1 , n = ∼8) that is isotypic with the lanthanide compounds [Ln(pmtz) 3 (H 2 O) 3 ]·(3 + n ) H 2 O (Ln = Ce-Nd). Dissolution and recrystallization of Pu1 in water yields the dinuclear compound {[Pu(pmtz) 2 (H 2 O) 3 ] 2 (μ-pmtz)} 2 (pmtz) 2 ·14H 2 O ( Pu2 ), which is isotypic with the lanthanide compounds {[Ln(pmtz) 2 (H 2 O) 3 ] 2 (μ-pmtz)} 2 (pmtz) 2 ·14H 2 O (Ln = Nd and Sm). Like their nine-coordinate ionic radii, the M-O and M-N bond lengths in Pu1 / Pu2 and Nd1 / Nd2 , respectively, are within error of one another. The Laporte-forbidden 4f → 4f and 5f → 5f transitions are also assigned in the UV-vis-NIR spectra for these f -element tetrazolate coordination compounds.