Nanoparticles, Thin Films and Surface Patterns from Spin‐Crossover Materials and Electrical Spin State Control

Rational Control of Spin-Crossover Particle Sizes: From Nano- to Micro-Rods of [Fe(Htrz)2(trz)](BF4)

“…From the SCO properties' point of view, the different particle batches exhibit a sharp transition with the presence of a hysteresis loop as expected for this compound (Figures 2 and 3) [13,14,17,18,21,22,25,27,28,35,36]. Within the investigated (t R , T R ) values, the SCO temperatures lay indeed within the known values for this compound with T 1/2up in the range of 372-390 K and T 1/2down in the range of 351-364 K. However, some small fluctuations of the SCO temperatures can be noted along with the (t R , T R ) variations (Figure 2).…”

“…These properties allow the consideration of the SCO materials relevant for use in display or switching devices as well as in smart pigments, for instance [9,10]. Furthermore, since these materials are also potential candidates for information storage, electronic devices, pressure or multimodal sensors [11,12], increasing attention has been paid to the elaboration of nanomaterials [13,14] including patterned [15] or continuous [16] thin films, nano-composites [17,18] or nanoparticles. The most convenient synthesis approach to get SCO particles is then based on the reverse-micelle method: microemulsions are used to confine the growth of the coordination network leading to small particles.…”

“…The influence of these parameters, which are the time and the temperature of the reaction, is examined for the compound [Fe(Htrz) 2 (trz)](BF 4 ) (Htrz = 1H-1,2,4-triazole and trz = deprotonated triazolato ligand). This well-known compound has been chosen for its chemical stability, its large hysteresis loop between 345 K and 385 K, together with clear evidence that it is possible to get diverse particle sizes from the nano-to the micro-range [13,14,17,18,21,27,28]. In this contribution, we therefore study the influence of these two major experimental parameters on the morphological aspects of the [Fe(Htrz) 2 (trz)](BF 4 ) particles and on their SCO properties.…”

Competing Phases Involving Spin-State and Ligand Structural Orderings in a Multistable Two-Dimensional Spin Crossover Coordination Polymer

“…sensors, actuators and memories. [14][15][16][17][18][19][20][21][22][23][24] This has led to an impressive growth of the SCO field in the last decade as a result of cross-seeding interaction between different areas of research ranging from coordination chemistry, materials science and solid state physics.…”

“…sensors, actuators and memories. [14][15][16][17][18][19][20][21][22][23][24] This has led to an impressive growth of the SCO field in the last decade as a result of cross-seeding interaction between different areas of research ranging from coordination chemistry, materials science and solid state physics.A pivotal current aspect that transcends the SCO research is the understanding of the elusive principles underlying cooperativity in multi-step spin transitions in the solid-state.Steps may occur when elastic forces favor competition between spatial periodicities of structural inequivalent SCO centers. For example, the presence of crystallographically distinct sites with different ligand field strengths.…”