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In this study we demonstrate that single-chain magnets (SCMs) can be assembled in gel phase and transferred intact on surface. We take advantage of a family of SCMs based on TbIIIions and nitronyl-nitroxides radicals functionalized with short alkyl chains known to form crystalline supramolecular nanotubes interacting with heptane acting as crystallizing solvent. When the radicals are functionalized with long aliphatic chains a robust gel is formed with similar structural and functional properties respect to its crystalline parent. Indeed, a small-angle X-ray scattering (SAXS) study unambiguously demonstrates that the gel is made of supramolecular nanotubes: the high stability of the gel allows the determination from SAXS data of precise nanotube metrics such as diameter, helical pitch and monoclinic cell of the folded 2D crystal lattice along the tube direction. Additionally, static and dynamic magnetic investigations show the persistence of the SCM behavior in the metallogel. Last, on-surface gelation provides thick films as well as sub-monolayer deposits of supramolecular nanotubes on surface as evidenced by atomic force microscopy (AFM) observations. This paves the road toward magnetic materials and devices made of SCMs profiting of their isolation on surface as individual chains.

Reactions in water of lanthanide chlorides with the sodium salt of 4,5-dichlorophthalate (dcpa2–) lead to two families of isostructural coordination polymers: family F1that gathers compounds with the general chemical formula [Ln2(dcpa)3(H2O)]∞with Ln = La–Gd (except Pm) and family F2that gathers compounds with general chemical formula [Ln2(dcpa)3(H2O)5·3H2O]∞with Ln = Tb–Lu plus Y. Heterolanthanide molecular alloys that contain both Eu3+and Tb3+ions have been prepared in both structural families. Their luminescence properties have been studied, especially from the brightness point of view. This study revealed that structural family F1provides molecular alloys that are much more luminescent than those of structural family F2. Therefore, a phase-induction strategy was followed that allowed the design of some molecular alloys (La/Tb/Eu and La/Dy) that are, to the best of our knowledge, among the most luminescent coordination polymers reported so far. This study opens the way to bright luminescent bar codes as well as to bright white luminescent lanthanide-based coordination polymers.

The reaction of bulky trimethylsilylanilide (N-TMSA) ligand with various lanthanide salts led us to isolate unusual and unique four-coordinate monomeric Ln(III) complexes which are challenging to isolate and not surprisingly rare in the literature. The single crystal X-ray diffraction unveils that all the complexes are monomeric and isostructural with the general molecular formula of [Ln(N-TMSA)3(THF)] where Ln = Dy (1) or Yb (2). Both complexes are found to possess distorted tetrahedral geometry. For all the complexes, detailed dc and ac susceptibility measurements were performed and both 1and 2show frequency-dependent out-of-phase susceptibility signals only in the presence of an optimum external magnetic field. The experimental observations are well supported by theoretical calculations and developed magneto-structural correlation using the various model complexes.