Photochemical separations and compositions

A method of separating metal complexes, the method comprising:

• providing a first metal complex and a second metal complex in a liquid, wherein the first metal complex and the second metal complex comprise a first ligand functionalized with an electron donor group;
• and
• exposing the liquid to light comprising one or more wavelengths sufficient to facilitate (i) the formation of an excited state on the first metal complex, (ii) an excited state electron transfer from the electron donor group of the first metal complex, and (iii) an irreversible chemical reaction of the electron donor group of the first metal complex, wherein the irreversible chemical reaction converts the first ligand of the first metal complex to a second ligand to form a modified first metal complex;
• wherein (i) the electron donor group comprises an alkylamine, an arylamine, or an ethanolamine, and (ii) the first ligand comprises acetylacetone (acac), dipicolinic acid (DPA), terpyridine (Tpy), diethylenetriaminepentaacetic acid (DTPA), or a combination thereof;
• and
• wherein (i) the first metal complex is a Cm(III) complex, and the second metal complex is an Am(III) complex, (ii) the first metal complex is an Am(III) complex, and the second metal complex is a Cm(III) complex, (iii) the first metal complex is an Ru(II) complex, and the second metal complex is an Fe(II) complex, or (iv) the first metal complex is an Fe(II) complex, and the second metal complex is an Ru(II) complex.