Search results for "Thermochromism"

showing 3 items of 33 documents

Spin crossover in soft matter

2014

Abstract This review article is devoted to the study of the spin crossover phenomenon in soft matter. Spin crossover compounds, though known for decades, bear the potential for practical applications in switching, sensing and display devices. Having arrived at a reasonable understanding of the spin transition process in solid and liquid states, one trend in this research field is to extend the knowledge into soft matter. The review begins with a brief description of Langmuir–Blodgett thin films based on FeII coordination compounds since it represents the first study of the spin crossover phenomenon in soft matter. The following section illustrates the FeII, FeIII and CoII complexes reported…

chemistry.chemical_classificationPhase transitionThermochromismValence (chemistry)Condensed matter physicsChemistrySpin transitionTautomerCoordination complexCondensed Matter::Soft Condensed MatterInorganic ChemistrySpin crossoverMaterials ChemistryCondensed Matter::Strongly Correlated ElectronsSoft matterPhysical and Theoretical ChemistryCoordination Chemistry Reviews
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A magnetic self-contained thermochromic system with convenient temperature range

2019

A new ionic liquid with sugar-based ligand has been prepared and used to coordinate cobalt(II), at low loading, in an ionic liquid solution. The system obtained reveals magnetic switching and marked thermochromism in solution/polymer films over a convenient temperature range (20–60 °C). This system is self-contained, devoid of any volatile substances, and reproducible over multiple thermal cycles. The colour change can be attributed to a change in the coordination geometry from octahedral (pink) at room temperature to tetrahedral (blue) on warming, monitored by 59Co NMR spectroscopy, which was used for the first time to study the change. This material may find applications in stimuli-respon…

chemistry.chemical_classificationThermochromismIonic liquids thermochromic systemMaterials science010405 organic chemistryAnalytical chemistrychemistry.chemical_elementNuclear magnetic resonance spectroscopyPolymercobalt complexesSettore CHIM/06 - Chimica OrganicaAtmospheric temperature range010402 general chemistry01 natural sciencesPollution0104 chemical scienceschemistry.chemical_compoundOctahedronchemistry13. Climate actionIonic liquidEnvironmental ChemistryCobaltCoordination geometry
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Preparation and Thermochromic Switching between Phosphorescence and Thermally Activated Delayed Fluorescence of Mononuclear Copper(I) Complexes

2020

Instructive, inexpensive, and environmentally friendly laboratory syntheses of two highly luminescent copper(I) complexes CuI(PPh3)2(pyR) (pyR = pyridine, 4-cyanopyridine) are described for second-year/upper-division undergraduate inorganic chemistry students. Both complexes exhibit bright thermally activated delayed fluorescence (TADF) at ambient temperature and phosphorescence at low temperature. The laboratory experiments familiarize the students with mechanochemical syntheses, cluster and complex formation, ligand substituent effects, and the fascinating phenomenon of luminescence thermochromism.

chemistry.chemical_classificationThermochromismchemistry.chemical_elementGeneral ChemistryPhotochemistryCopperFluorescenceFluorescence spectroscopyEducationCoordination complexchemistry.chemical_compoundchemistryPyridinePhosphorescenceLuminescenceJournal of Chemical Education
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