Design of magnetic organic molecules and organic magnets: Experiment, theory and computation with application and recent advances

Abstract

We begin by reviewing the early developments in the synthesis of high-spin organic molecules and the simultaneous rationalization of the ground states of high spin. A number of chemists contributed, most notably Gomberg and Hückel, and theoreticians like Coulson, Rushbrooke, Longuet-Higgins, McConnell, Hoffmann etc. The subject achieved maturity after 1970. Theoretical advances were made. Methods of calculations such as multi-configuration self-consistent-field, coupled cluster, density functional, and broken-symmetry methodologies prospered. These were in turn increasingly used in magnetic studies on organic species. Armed with the concepts, theory, and calculational methodologies, both experimental and theoretical researches involved the design of fascinating magnetic organic molecules, especially since 2000. The effects of varying chemical structures, aromaticity, presence of heteroatoms, effects of hydrogen bonding and tautomerism, stereochemical aspects, and the formation of polymers, extended systems and crystals were all considered. A multitude of applications was found in the form of single molecule magnets, photomagnets and photomagnetic switches, spin cross-over, excitation and redox process assisted magnetic activation, spintronics, and so on. A spectacular growth in applications has been witnessed in the last decade. It has been accompanied by speculative and predictive advances in theory and computational investigation.

Keywords

• High-spin
• Molecular magnets
• Condensed phase
• Extended systems
• Spintronics