fdp magnets

Tremendous amount of work on molecular-based magnets has been reported in the literature. - Such magnetic compounds and particularly zero-dimensional clusters (so-called Single Molecule - Magnets, SMMs) are currently subjects to spectacular interest since original magnetic materials - with high-density information storage potential can be anticipated. Different strategies along with - flourishing experimental techniques have been developed to investigate the unusual physical - properties of these magnetic molecules and nanowires (Single Chain Magnets, SCMs). Even - though these systems are not strictly 3D ordered compounds, the presence of hysterisis loop - below a blocking temperature is a reminiscence of classical magnets. - With this goal in mind, different synthetic routes - have been considered and are currently subject to intense work. - A detailed understanding of the magnetic phenomena in sophisticated - architectures becomes rapidly unreachable since different subtle mechanisms are likely to - compete. The traditional rationalization proceeds through the use of the well-known Heisenberg - Hamiltonian which introduces effective magnetic coupling constants J. A more sophisticated - approach calls for the participation of anisotropic contributions D and E in a generalized picture. - Even though these phenomenological treatments have turned out to be extremely valuable in a - comprehensive analysis of experimental data, the underlying physical phenomena still deserve - special attention. In particular, how much the respective exchange and anisotropy terms have the - ability to account for such intricate interactions is questionable. Besides, to what extent bridging - ligands remain diamagnetic (innocent) as magnetic interactions between metallic centres are - turned on. Even if such partitioning between physical effects and within magnetic moieties may - not be straightforward, one can think of promising synthetic routes of magnetic systems. - The fdp magnets project we plan to pursue relies on complementary experimental and - theoretical skills. Considering the growing interest for 4f-based materials and their potential - applications, there is a real need for theoretical analysis. Even though some methodologies and - phenomenological approaches are available, DFT as well as ab initio techniques would be - extremely insightful in the understanding of heavy-elements magnetic properties. Our project - combines the synthesis of original and well-characterized prototype objects and the - implementation of demanding calculations. Some architectures of ours are already available for - theoretical inspection. However, specific objects which should hold controlled magnetic - interactions will be prepared in the future to get a thorough understanding of the microscopic - interactions. The association of f, d and p spin carriers within the same molecular objects is a - challenging synthetic target, while understanding their physico-chemistry and more specifically - their magnetic properties is an attractive theoretical problem. - ...