Tuning spin crossover behavior in the [Fe3(µ-L)6(H2O)6]6- trimer: dilution and contracation effects (L = 4-(1,2,4-triazol-4-yl) ethanedisulfonate)

Entity: Universitat Rovira i Virgili (URV)

Confidenciality: No

Education area(s): Nanociència, Materials i Processos - Tecnologia Química de Frontera 

Title in different languages: Tuning spin crossover behavior in the [Fe3(µ-L)6(H2O)6]6- trimer: dilution and contracation effects (L = 4-(1,2,4-triazol-4-yl) ethanedisulfonate)

Abstract: Abstract: In spin crossover (SCO) systems, external stimuli (temperature, pressure, light irradiation, etc.) may trigger a transition from the low spin ground state (LS) to the high spin excited state (HS), which is metastable. The characteristics of this switchability (shape, energy difference between states, cooperativity, external stimuli response…) are determined by the crystal structure in the solid state and, therefore, may be tunned by chemistry design. The (Me2NH2)6[Fe3(μ-L)6(H2O)6]·nH2O (L=4-(1,2,4-triazol-4-yl) ethanedisulfonate) has shown extraordinary SCO features, at very high temperatures and bistability in a long temperature range, with a hysteresis over 90 K. In this work, we have studied the effect on the SCO phenomena provoked by modifications on the crystal structure of the material: on one end, by dilution in a non-SCO isostructural crystal; on the other end, through methatesis with another contracation. Our results indicate that the memory effect may be tuned by contracation substitution and, remarkably, that SCO hysteresis still remains in ultradiluted samples, suggesting the appearance of single molecule memory effect.

Subject: Química

Academic year: 2016-2017

Language: Anglès

Work's public defense date: 2017-09-12

Subject areas: Chemistry

Student: Nieto Castro, David

Department: Química Analítica i Química Orgànica

Creation date in repository: 2018-03-12

TFM credits: 24

Keywords: spin crossover, magnetism, molecular hysteresis

Title in original language: Tuning spin crossover behavior in the [Fe3(µ-L)6(H2O)6]6- trimer: dilution and contracation effects (L = 4-(1,2,4-triazol-4-yl) ethanedisulfonate)

Access Rights: info:eu-repo/semantics/closedAccess

Project director: Galán-Mascarós, Jose Ramón