Ferroin sulfate?
Although I started this article, I now regret that I did not assign the full formula for a real salt vs an ion.  Since the sulfate is the most common salt of ferroin, I suggest that we either (1) move the article to Iron(II) tris(phenanthroline) sulfate (seems cumbersome) or (2) tweak the current article to focus mainly on the sulfate (the same CAS#) but this way we can discuss solubility, structure, prep, while acknowledging that the properties in soln are independent of the anion.