Influence of ligands on the electronic and magnetic properties of Fe porphyrin in gas phase and on Cu(001)

Abstract

External electric field effects on electronic and magnetic properties at molecule-metal interfaces: Cuphthalocyanine adsorbed on Fe(001) surface J. Appl. Phys. 114, 083702 (2013); 10.1063/1.4819085 Adsorption geometry, conformation, and electronic structure of 2H-octaethylporphyrin on Ag(111) and Fe metalation in ultra high vacuum Time dependent density functional theory study of the near-edge x-ray absorption fine structure of benzene in gas phase and on metal surfaces

Electronic Structure of Iron Porphyrin Adsorbed to the Pt(111) Surface

“…The Hubbard U term was used to describe the d-states in iron . We employed a U eff = U – J = 3.0 eV, as it has been shown to accurately reproduce the electronic and magnetic structure of FeP in the gas phase. , In addition, a U eff of 3.0 eV has been successfully employed to study the adsorption of Fe­(II) porphyrins to surfaces. ,, Benchmark calculations showed that a U eff = 3.0 eV yielded the correct S = 1 ground spin state for FeP for all of the functionals considered herein.…”

“…Nearly all 3d metals can be incorporated into the macrocycles, and they easily form noncovalent 2D assemblies on flat, crystalline surfaces, − as well as 3D metal–organic frameworks. They have thus become a prototypical system for the study of coordination effects and molecular spintronics, as is evident by the large number of studies of metalated porphyrins on surfaces alone. − ,− The local conductivity of the molecules correlates with the spin state of the central metal atom, ,,, and local probes, specifically scanning tunneling microscopes (STM), can be used to detect and manipulate the local magnetic properties. , Other effects conveniently observable on 2D porphyrin layers are adsorbate and substrate effects, such as superexchange between the metal centers through the substrate …”

“…For example, density functional theory (DFT) calculations predicted that the HS state will be preferred when iron porphyrins are physisorbed on Au(111), chemisorbed to various magnetic substrates including Co(001), Ni(001), Ni(110), and Ni(111), or deposited at a divacancy site in a graphene lattice . However, DFT predicts that the S = 1 state will be maintained upon adsorption to the Cu(001) surface . Moreover, DFT calculations have shown that the spin state of the related manganese­(II) porphine molecule can be perturbed via adsorption to the Au(111) surface, and application of an electric field to this system also alters its magnetic properties …”

Deposited Transition Metal‐Centered Porphyrin and Phthalocyanine Molecules: Influence of the Substrates on the Magnetic Properties

“…Furthermore, a deformation or buckling of the substrate next to the molecule is observed which is particularly pronounced for Cl and O ligands, while with O 2 as a ligand, the surface is much less affected. Indicating that for the dimer the interaction with the substrate is weaker than in the case of atomic Cl or O even though the adsorption distance is very similar, 2.28 Å (2.23 Å) with O 2 (O) for Cl the average distance between substrate and Fe is even larger (2.50 Å) [14]. In conclusion, it has been shown that the spin moment of FeP or the iron center itself can be tackled by the choice of the ligand in gas phase as well as on nonmagnetic Cu(001), whereby the changes for deposited molecules are even more expressed.…”

“…Having seen that for a sub-monolayer coverage of Fe OEP on Cu(001) 50% of the Cl atoms which remain after deposition of the surface is sufficient to cause significant changes in the magnetic behavior, a detailed study of possible ligands and their influence on the magnetic properties has been performed for free and deposited FeP molecules [14]. In gas phase, the influence of various combinations of porphyrin or phthalocyanine and ligands (axial or peripheral) has been investigated.…”