Luminescence detection of cation exchange in Na3[Eu(2,6-pyridinedicar☐ylato)3]

The exchange of several other cations for the Na+ ions in Na3[Eu(2,6-pyridinedicar☐ylato)3] was investigated using Eu3+ ion luminescence spectroscopy. Monovalent, divalent, and trivalent metal ions, as well as the monovalent ammonium ion, replaced the Na+ ion via mass action to form various salts with the Eu(2,6-pyridinedicar☐ylato)3-3 complex anion. The detection of the cation exchange was achieved because of the sensitivity of Eu3+ ion luminescence to the near environment of the Eu3+ ion.