Abstract The reactions of the lithium salt of (S)-2-(1,8-naphthalimido)-3-hydroxypropanoate (L-ser(-)), an enantiopure carboxylate ligand containing a 1,8-naphthalimide pi center dot center dot center dot pi stacking supramolecular tecton and an alcohol functional group, with La(NO3)(3), Ce (NO3)(3), SmCl3, Eu(NO3)(3), Gd(NO3)(3), Tb(NO3)(3), and Dy(NO3)(3) under solvothermal conditions (water/ethanol) produced single crystals (characterized by single-crystal X-ray crystallography) of [La-3(L-ser)(8)-(OH)(H2O)]center dot(H2O,EtOH)(x) (1), [Ce-3 (L-ser)(8)(OH)(H2O)]center dot(H2O,EtOH)(x) (2), [Sm-3(L-ser)(8)(OEt)]center dot(H2O,EtOH)(x) (3), [Eu-3(L-ser)(8) (OEt)]center dot(H2O,EtOH)(x) (4), [Gd-3(L-ser)(8)(OEt)]center dot(H2O,EtOH)(x) (5), [Tb-3 (L-ser)(8)(OEt)]center dot(H2O,EtOH)(x) (6), and [Dy-3(L-ser)(8)(OEt)]center dot(H2O,EtOH)(x) (7), respectively. Mixed-metal complexes [Ce2.3Tb0.7(L-ser)(8)(OH)]center dot(H2O,EtOH)(x) (8), [Gd0.4Tb2.6(L-ser)(8)(OEt)]center dot(H2O,EtOH)(x) (9), and [Ce1.4Gd0.3Tb1.3(L-ser)(8)(OH)]center dot(H2O,EtOH)(x) (10) were prepared by using two or more types of lanthanides in the solvothermal reactions (additional mixed-metal complexes were prepared and characterized by ICP-MS). Single crystals of compounds 1-10 are isostructural: trinuclear, carboxylate-bonded helicates organized by the non-covalent, pi center dot center dot center dot pi stacking interactions of the 1,8-naphthalimide groups into intertwined M helices, with a pitch of 56 angstrom, that are further arranged into a three-dimensional supramolecular framework by additional pi center dot center dot center dot pi stacking interactions. Magnetic measurements of several compounds were as expected for the metal(s) present, indicating no significant interactions between metals within the helicates. The Ce complex 2 showed weak antiferromagnetic ordering below 50 K. All of the complexes, with the exception of 2, showed luminescence based on the 1,8-naphthalimide group. Complex 2 has no emission, and complexes with mixed Ce/Tb ratios showed significant quenching of the naphthalimide-based luminescence, as quantitated with solid-state, absolute quantum yield measurements of these mixed-metal and the pure metal complexes. Lanthanide-based luminescence was only observed for the Eu complex 4.