Hierarchical Self‐Assembly of Supramolecular Spintronic Modules into 1D‐ and 2D‐Architectures with Emergence of Magnetic Properties

Abstract

Hierarchical self-assembly of complex supramolecular architectures allows for the emergence of novel properties at each level of complexity. The reaction of the ligand components A and B with Fe(II) cations generates the [2x2] grid-type functional building modules 1 and 2, presenting spin-transition properties and preorganizing an array of coordination sites that sets the stage for a second assembly step. Indeed, binding of La(III) ions to 1 and of Ag(I) ions to 2 leads to a 1D columnar superstructure 3 and to a wall-like 2D layer 4, respectively, with concomitant modulation of the magnetic properties of 1 and 2. Thus, to each of the two levels of structural complexity generated by the two sequential self-assembly steps corresponds the emergence of novel functional features.

Solution and solid state properties of Fe(III) complexes bearing N-ethyl-N-(2-aminoethyl)salicylaldiminate ligands

“…This included the discovery of several new examples of SCO compounds [3,[9][10][11], the explanation of different types of SCO profiles [4,12] and the modification of SCO compounds to increase cooperativity and to direct their application into materials science [13]. Scientists have developed SCO networks [14][15][16], frameworks [17][18][19], gels [20][21][22], liquid crystals [23][24][25], nanoparticles and nanocrystals [26][27][28][29], nanowires [30], thin films [31][32][33] and have also applied patterning techniques to fabricate SCO devices [34]. Among complexes displaying SCO, [Fe(salEen) 2 ] + derivatives (salEen = N-ethyl-N-(2-aminoethyl)salicylaldiminate) are known to undergo thermal SCO sensitive to unit cell contents and supramolecular packing in the crystal [35].…”

Challenges and breakthroughs in recent research on self-assembly

“…Garca-Zarracino and Höpfl reported formation of polymeric and trinuclear macrocyclic hybrids with porous solid-state structures through self-assembly of diorganotin(IV) oxides [513]. Lehn, Gtlich, and coworkers described formation of molecular-grid-type hierarchical self-assembled structures as spintronic modules [514]. Fabrication of colloidal nanoparticles [515] and crystalline rods was accomplished by Mirkin and coworkers [516].…”

The Development of Spin‐Crossover Research

“…110 4 ] n 12+ , that displayed modification of the magnetism such that LS forms become stabilised, at a particular temperature, compared to the starter. 112 The very gradual and nonhysteretic spin-transitions persisted in these extended structures and their functionality as supramolecular spintronic modules was envisaged.…”