Structural variability in neptunium(V) oxalate compounds:: Synthesis and structural characterization of Na2NpO2(C2O4)OH•H2O

Reaction of a Np-237(V) stock solution in the presence of oxalic acid, calcium chloride, and sodium hydroxide under hydrothermal conditions produces single crystals of a neptunium(V) oxalate, Na2NpO2(C2O4)(OHH2O)-H-.. The structure consists of one-dimensional chains running down the a axis and is the first example of a neptunium(V) oxalate compound containing hydroxide anions.