Magnetic molecules created by hydrogenation of Polycyclic Aromatic Hydrocarbons

TL;DR

This paper demonstrates that selective hydrogenation of polycyclic aromatic hydrocarbons can produce stable high-spin magnetic molecules, offering a novel approach to organic magnetism.

Contribution

It introduces a new method for creating magnetic organic molecules through hydrogenation, supported by quantum chemical calculations.

Findings

Stable high-spin species are achievable in hydrogenated PAHs.

Ground state spins follow Hund's rule and Lieb's theorem.

Hydrogenation opens new pathways for organic magnetic materials.

Abstract

Present routes to produce magnetic organic-based materials adopt a common strategy: the use of magnetic species (atoms, polyradicals, etc.) as building blocks. We explore an alternative approach which consists of selective hydrogenation of Polycyclic Aromatic Hydrocarbons. Self-Consistent-Field (SCF) (Hartree-Fock and DFT) and multi-configurational (CISD and MCSCF) calculations on coronene and corannulene, both hexa-hydrogenated, show that the formation of stable high spin species is possible. The spin of the ground states is discussed in terms of the Hund rule and Lieb's theorem for bipartite lattices (alternant hydrocarbons in this case). This proposal opens a new door to magnetism in the organic world.