Tetranuclear Lanthanide Complexes Supported by Hydroxyquinoline‐Calix[4]arene‐Ligands: Synthesis, Structure, and Magnetic Properties of [Ln <sub>4</sub> (H <sub>3</sub> L) <sub>2</sub> (µ‐OH) <sub>2</sub> (NO <sub>3</sub> ) <sub>4</sub> ] (Ln = Tb, Dy, Yb) and [Dy <sub>2</sub> (H <sub>4</sub> L) <sub>2</sub> (NO <sub>3</sub> )](NO <sub>3</sub> )
European journal of inorganic chemistry