Tetra­kis(μ-naphthalene-1-acetato-1:2κ(2) O:O′)bis­(naphthalene-1-acetato)-1κ(2) O,O′;2κ(2) O,O′-bis­(1,10-phenanthroline)-1κ(2) N,N′;2κ(2) N,N′-europium(III)samarium(III)

In the title compound, [EuSm(C(12)H(9)O(2))(6)(C(12)H(8)N(2))(2)], the metal site is statistically occupied (50:50) by Eu and Sm atoms, forming a centrosymmetric complex. The metal site is nine-coordinate, in a distorted monocapped square-anti­prismatic coordination geometry. Mol­ecules are linked into three chains by C—H⋯π interactions and C—H⋯O hydrogen bonds. The combination of these chains generates a three-dimensional framework structure. One of the bridging naphthalene-1-ace­tate ligands was found to be disordered over two sites; the site occupancies for the naphthylmethyl group refined to 0.628 (14) and 0.372 (14).