Secondary interactions occur beyond the primary coordination sphere and can influence the performance of single molecule magnets (SMMs). This article highlights the role that secondary interactions play in the synthesis and performance of SMMs.

Structural, magnetic, and computational analysis of a series of Ni ₄ defective dicubanes is described.

Two series of tetradentate tripodal di-pyridine-based receptors designed to bind Be²⁺ cations have been studied in the aqueous phase at the B3LYP/6-311++G(d,p) computational level. The first series comprise simple tetrahedral receptors; the second series incorporates additional scaffolding groups capable of second sphere hydrogen-bonding in order to more finely tune the binding strength towards the Be²⁺ cation. Out of the five ligand candidates, one containing a tri-pyridyl N-donor along with a phenolato O-donor (L1) exhibited a significant improvement in binding energy stabilisation (47.8 kJ mol⁻¹) towards the Be²⁺ cation in the presence of second-sphere H-bonding interactions.

Four new non-macrocyclic triangular Ni ₃ M (M = La ^III , Eu ^III , Gd ^III , or Ba ^II ) complexes with planar Ni ₃ MO ₆ cores are reported, including structural and magnetic characterisation.

We report the synthesis and characterization of seven new tetranuclear 3d–4f complexes derived from the 3:3:1 reaction of 1,4-diformylnaphthalene-2,3-diol (H₂L) with copper(II) nitrate and a lanthanide salt, Ln = Tb [L₃Cu₃TbCl₂(NO₃)₂(H₂O)₂] (C1), Ho [L₃Cu₃HoCl₃(H₂O)₃(MeOH)](H₂O) (C2), Er [L₃Cu₃ErCl₃(H₂O)_3.5(MeOH)_0.5](H₂O) (C3), Gd [L₃Cu₃Gd(NO₃)₂(H₂O)₂(MeOH)](NO₃) (C4), Dy [L₃Cu₃Dy(NO₃)₂(H₂O)₂(MeOH)](NO₃) (C5), Yb [L₃Cu₃Yb(NO₃)₂(H₂O)₂(MeOH)](NO₃) (C6), and La [L₃Cu₃La(NO₃)₂(H₂O)₂(MeOH)](NO₃) (C7). Structural elucidation showed that the self-assembly using the acyclic ligand system was successful for all seven complexes, which exhibit the same near-planar Cu₃LnO₁₂ core. Five complexes (C1, C2, and C4–C6) were magnetically characterized at 300 K and 1.8 K. Complexes C1, C4, and C5 were observed to have ferromagnetic ground states and showed appreciable frequency dependence in their AC magnetic measurements, which yielded effective barriers between 7.82(4) and 13.2(3) K, confirming the presence of single-molecule magnet properties.