Magnetic Phase Transitions in a Ni ₄ O ₄ ‐Cubane‐Based Metal–Organic Framework

An unprecedented spin cluster‐based network architecture {[Ni II 2 (pdaa)(OH) 2 (H 2 O)] n (H 2 pdaa=1,4‐phenylene diacetic acid)}, comprising 1D linear chains of Ni II ions crosslinked via Ni 4 O 4 cubanes, forms under hydrothermal conditions; this 3D coordination network exhibits magnetic ordering at 23.9 K as well as a second magnetic ordering process at 2.8 K likely associated with a structural phase...