Magnetic Interplay between π-Electrons of Open-Shell Porphyrins and d-Electrons of Their Central Transition Metal Ions.
Qiang SunLuis M MateoRoberto RoblesPascal RuffieuxGiovanni BottariTomás TorresRoman FaselNicolás LorentePublished in: Advanced science (Weinheim, Baden-Wurttemberg, Germany) (2022)
Magnetism is typically associated with d- or f-block elements, but can also appear in organic molecules with unpaired π-electrons. This has considerably boosted the interest in such organic materials with large potential for spintronics and quantum applications. While several materials showing either d/f or π-electron magnetism have been synthesized, the combination of both features within the same structure has only scarcely been reported. Open-shell porphyrins (Pors) incorporating d-block transition metal ions represent an ideal platform for the realization of such architectures. Herein, the preparation of a series of open-shell, π-extended Pors that contain magnetically active metal ions (i.e., Cu II , Co II , and Fe II ) through a combination of in-solution and on-surface synthesis is reported. A detailed study of the magnetic interplay between π- and d-electrons in these metalloPors has been performed by scanning probe methods and density functional theory calculations. For the Cu and FePors, ferromagnetically coupled π-electrons are determined to be delocalized over the Por edges. For the CoPor, the authors find a Kondo resonance resulting from the singly occupied Co II d z 2 orbital to dominate the magnetic fingerprint. The Fe derivative exhibits the highest magnetization of 3.67 μ B (S≈2) and an exchange coupling of 16 meV between the π-electrons and the Fe d-states.
Keyphrases
- transition metal
- aqueous solution
- density functional theory
- molecular dynamics
- molecularly imprinted
- water soluble
- minimally invasive
- quantum dots
- metal organic framework
- energy transfer
- high throughput
- electron microscopy
- single cell
- human health
- mass spectrometry
- monte carlo
- electron transfer
- ionic liquid
- liquid chromatography
- visible light