VOLURAD · Single-molecule magnets based on the orbitally-degenerate spin centers and stable organic radicals complexes
FP7 — People (Marie Curie Actions)
- Duration
- 2012-07-23 → 2014-07-22
- EU contribution
- €269,096
- Participants
- 1
- Scheme
- MC-IIF
Lines connect the coordinator with its partners.
Results in brief
Single-molecule magnets based on the orbitally-degenerate spin centers and stable organic radicals complexes
Single-Molecule Magnets are molecule made of an organic and metal part that behave like magnets on the molecular level. The magnetism is fundamentally different from the traditional magnets. Indeed, such molecules exhibit “quantum properties”. This attracted much attention as they open the way for extra miniaturization with perspective of application in information storage and processing. The objectives of the project were to raise the blocking (operating) temperature of such materials by using an approach based on heterospin systems. The work performed during the two years period has followed the working plan given in the proposal. Accordingly, we synthesised several new polynuclear complexes assembling 4d (Ru) or 5d (Os, Re) with 3d metal ions and polynuclear complexes assembling 3d metal ions and nitroxide radicals. Most of these new compounds have been structurally characterized by x-ray diffraction on single crystal and their magnetic properties have been investigated as describe below. Publication of the result is under submission to international reviews. The works we have performed belong to basic researches but it aims to future applications in the field of information processes. Indeed, SMM have been proven to be relevant for applications in quantum computing and may satisfy the societal demand for mass data mining. Our researches were multidisciplinary and our result interest the all field of molecular based materials, inorganic and physical chemistry as well as nanotechnology. Our results promote synergy and added value in the field of chemistry and establish a foundation for high-quality research.
Data: CORDIS, © European Union
Project objective
The finding some polynuclear complexes can behave like magnets on the molecular level attracted much attention, opening perspectives for their applications in processing devices or for high density information storage carriers. To manifest single-molecule magnet (SMM) behaviour a polynuclear complex should have a high-spin ground-state and strong negative anisotropy (D). The energy barrier, U, separating two spin orientations (up-down) is proportional to the product of │D│ and square of spin, S. Therefore the larger the D and S values are the higher the U barriers should be and the longer the magnetization might be blocked. However, such single-molecule magnetization is so far only observed at temperatures too low to allow an application.The project aims to rise the blocking temperature by increasing the U. Our approach is based on heterospin polynuclear complexes assembling involving orbitally-degenerated 4d, 5d metal centres (Os, Ru) and 3d metal ions or/and nitroxide radicals. If the utilisation of the first guaranties the strong anisotropy, the use of the stable radicals as ligands and bridges assures well isolated high spin ground-state owing to the strong exchange interactions between spin carriers. The synthesis work will be complemented with structural analysis and magnetic studies of these systems to elucidate the magnetic interactions as well the magnetic anisotropy in conjunction with theoretical magneto-structural analysis. A major goal of the project is to discover some rules for the rational design of polynuclear cluster systems with elevated blocking temperatures. The project results will document the coordination chemistry of 4d and 5d ions with nitroxides, a field lacking of fundamental results. The complexes will bring experimental opportunity to test and improve theoretical models. The project might be considered as a step toward molecular spintronics. Prototypes of devices could be envisioned if the right property shows up at liquid nitrogen.
Original text from CORDIS.
Participants
- UNIVERSITE LYON 1 CLAUDE BERNARD · Villeurbanne CedexCoordinatorFrance
Links
Data: CORDIS, © European Union