Fig. 4: Molecular structures of [Dy(L¹)] and [Dy(L²)] in the solid state.

In both structures, the ligand coordinated to the central Dy^III cation with four ring nitrogen donors and four carboxylate donors. The view highlights the absolute configuration of the proline ring. Thermal ellipsoids were set at 50% probability. A [Dy(L¹)] contains 2R,3S,4S configuration of the proline ring (green shading) and the chelate adopts ∆λλλλ square antiprismatic (SA) conformation. For detailed information, see Supplementary Figs. 1–3. B [Dy(L²)] contains 2S,3R,4S configuration of the proline ring (violet shading) and the chelate adopts ∆δδδδ twisted square antiprismatic (TSA) conformation. For detailed information, see Supplementary Figs. 5–7.