Gas-phase coordination complexes of U(VI)O2(2+), Np(VI)O2(2+), and Pu(VI)O2(2+) with dimethylformamide.

Electrospray ionization of actinyl perchlorate solutions in H(2)O with 5% by volume of dimethylformamide (DMF) produced the isolatable gas-phase complexes, [An(VI)O(2)(DMF)(3)(H(2)O)](2+) and [An(VI)O(2)(DMF)(4)](2+), where An = U, Np, and Pu. Collision-induced dissociation confirmed the composition of the dipositive coordination complexes, and produced doubly- and singly-charged fragment ions. The fragmentation products reveal differences in underlying chemistries of uranyl, neptunyl, and plutonyl, including the lower stability of Np(VI) and Pu(VI) compared with U(VI).