Table 13.2 summarizes this discussion in terms of the oxidation states shown by the d elements, and the stabilities of these. The general behaviour is also illustrated by Tables 13.3 to 13.5 which give the oxides, fluorides and other halides of the transition elements. A stable state will show all these compounds while a strongly oxidizing state will be more likely to have a fluoride than an iodide; similarly, a reducing state will be more likely to show a heavier halide than a fluoride. In fact, the highest oxidation state of a transition metal is typically obtained in an anionic complex, particularly oxides and fluorides. As a good illustration of this, the AgF4 and NiF¿~ ions have been known for some time, but the parent binary fluorides AgF3 and NiF4 have only recently been synthesized as highly reactive, polymeric solids. A promising route for the synthesis of these high oxidation state compounds involves fluoride-ion removal from the anionic fluoro-complex by a powerful fluoride ion acceptor such as AsF5.