<p>A series of aluminum-lanthanide-sodium 12-metallacrown-4 compounds with either 4-hydroxybenzoate or 4-aminobenzoate has been synthesized and characterized by FT-IR and single-crystal X-ray diffraction. The five LnNa(X)₄[12-MC_{Al(III)N(shi)}-4] compounds, where Ln^III is Gd (<b>1</b>), Dy (<b>2</b>), Tb (<b>4</b>), or Yb (<b>3</b> and <b>5</b>), X is 4-hydroxybenzoate (<b>1</b>–<b>3</b>) or 4-aminobenzoate (<b>4</b> and <b>5</b>), and shi³⁻ is salicylhydroximate, are practically isostructural with only subtle changes to the metallacrown (MC) framework upon changing the components of the MC. The supramolecular metallacrowns possess three separate metal binding sites. The domed MC framework is generated by four ring Al^III ions and four salicylhydroximate ligands, which also produce a central cavity. The MC cavity then binds both Ln^III and Na⁺ ions but on different faces of the MC scaffold. The Ln^III ion is located on the convex side of the dome, while the Na⁺ ion is bound to the concave underside. While the structural features of the MCs such as the size of the central MC cavity are similar regardless of the identity of Ln^III ion or carboxylate anion, the radius of the Ln^III ion dictates how closely the ion may approach the MC cavity. For <b>1</b>–<b>3</b> the larger Gd^III ion resides 1.53 Å from the mean plane of the oxime oxygen atoms (O_oxMP) of the MC cavity, while the smaller Yb^III ion resides 1.48 Å from the O_oxMP. For <b>4</b> and <b>5</b>, the larger Tb^III ion resides 1.54 Å from the O_oxMP, while the Yb^III ions of <b>5</b> reside 1.47 and 1.48 Å from the O_oxMP.</p> Graphical abstract <p></p>