Interplay between a crystal's shape and spatiotemporal dynamics in a spin transition material
FOURATI, Houcem
Groupe d'Etude de la Matière Condensée [GEMAC]
Laboratoire de Physique Appliquée [Université de Sfax] [LPA]
Groupe d'Etude de la Matière Condensée [GEMAC]
Laboratoire de Physique Appliquée [Université de Sfax] [LPA]
MILIN, Eric
Université de Brest [UBO]
Chimie, Electrochimie Moléculaires et Chimie Analytique [CEMCA]
Université de Brest [UBO]
Chimie, Electrochimie Moléculaires et Chimie Analytique [CEMCA]
SLIMANI, Ahmed
Laboratoire des Matériaux Multifonctionnels et Applications [Université de Sfax] [LaMMA]
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Laboratoire des Matériaux Multifonctionnels et Applications [Université de Sfax] [LaMMA]
FOURATI, Houcem
Groupe d'Etude de la Matière Condensée [GEMAC]
Laboratoire de Physique Appliquée [Université de Sfax] [LPA]
Groupe d'Etude de la Matière Condensée [GEMAC]
Laboratoire de Physique Appliquée [Université de Sfax] [LPA]
MILIN, Eric
Université de Brest [UBO]
Chimie, Electrochimie Moléculaires et Chimie Analytique [CEMCA]
Université de Brest [UBO]
Chimie, Electrochimie Moléculaires et Chimie Analytique [CEMCA]
SLIMANI, Ahmed
Laboratoire des Matériaux Multifonctionnels et Applications [Université de Sfax] [LaMMA]
Laboratoire des Matériaux Multifonctionnels et Applications [Université de Sfax] [LaMMA]
ABID, Younes
Groupe d'Etude de la Matière Condensée [GEMAC]
Laboratoire de Physique Appliquée [Université de Sfax] [LPA]
< Leer menos
Groupe d'Etude de la Matière Condensée [GEMAC]
Laboratoire de Physique Appliquée [Université de Sfax] [LPA]
Idioma
en
Article de revue
Este ítem está publicado en
Physical Chemistry Chemical Physics. 2018, vol. 20, n° 15, p. 10142-10154
Royal Society of Chemistry
Resumen en inglés
We investigated by means of optical microscopy (OM) the spatiotemporal features of the thermo-induced spin transition of [Fe(2-pytrz)2{Pd(CN)4}]·3H2O (1) (2-pytrz = 4-(2-pyridyl)-1,2,4,4H-triazole) single crystals having ...Leer más >
We investigated by means of optical microscopy (OM) the spatiotemporal features of the thermo-induced spin transition of [Fe(2-pytrz)2{Pd(CN)4}]·3H2O (1) (2-pytrz = 4-(2-pyridyl)-1,2,4,4H-triazole) single crystals having two different shapes (triangle and rectangle). While magnetic and calorimetric measurements, performed on a polycrystalline material, showed the respective average heating and cooling transition temperatures of (Tdown1/2 ∼ 152 K, Tup1/2 ∼ 154 K) and (Tdown1/2 ∼ 160.0 K, Tup1/2 ∼ 163.5 K), OM studies performed on a unique single crystal revealed significantly different switching temperatures (Tdown1/2 ∼ 152 K and Tup1/2 ∼ 162 K). OM investigations showed an interface spreading over all crystals during the spin transition. Thanks to the color contrast between the low-spin (LS) and the high-spin (HS) states, we have been able to follow the real time dynamics of the spin transition between these two spin states, as well as access the thermal hysteresis loop of each single crystal. After image processing, the HS–LS interface's velocity was carefully estimated in the ranges [4.4–8.5] μm s−1 and [2.5–5.5] μm s−1 on cooling and heating, respectively. In addition, we found that the velocity of the interface is shape-dependent, and accelerates nearby the crystal's borders. Interestingly, we observed that during the propagation process, the interface optimizes its shape so as to minimize the excess of elastic energy arising from the lattice parameter misfit between the LS and HS phases. All of these original experimental results are well reproduced using a spatiotemporal model based on the description of the spin-crossover problem as a reaction diffusion phenomenon.< Leer menos
Proyecto ANR
Bistabilité magnétique dans de nouveaux systèmes moléculaires à base de ligands anioniques pontants
Orígen
Importado de HalCentros de investigación