CoPc 2D and 1D Arrangement on a Ferromagnetic Surface

Abstract

We investigated the growth and electronic properties of Co-phthalocyanine (CoPc) molecule deposited on iron film with different structures (pseudomorph-fcc and bcc) and on iron nanowires by scanning tunnelling microscopy and X-ray absorption spectroscopy (XAS). CoPc molecules self-assemble in a two-dimensional (2D) arrangement with the molecular plane parallel to the iron surfaces, and the local order is lost after the first layer. The molecule-ferromagnet interaction causes the broadening of Co and N unoccupied molecular states as well as different electronic distribution of N states as a function of the atomic structure of iron surface. The ferromagnetic coupling between the molecule and the iron film is dominated by the electronic interaction between Co and the first Fe layer. CoPc 2D arrangement turns into 1D by using as a template the iron nanowire grown on a facet surface of oxidized Cu(332) surface. CoPc molecules interact weakly with the iron nanowires manifesting a substantial Co 3dz spectral feature in XAS spectrum and the possibility of a magnetic interaction between Co moment and iron nanowires. Both CoPc 2D and 1D arrangements can open up new interesting scenarios to tune the magnetic properties of hybrid interfaces involving metallorganic molecules.

Magnetic configurations of open-shell molecules on metals: The case of CuPc and CoPc on silver

“…An in-depth understanding of the electronic structure and magnetic properties of surface-adsorbed organic molecules is of direct relevance for and key to molecular spintronics [1][2][3][4][5][6][7][8][9][10][11]. Naturally, the deposition of nonmagnetic, closedshell molecules on magnetic substrates can result in a magnetic polarization of the molecule [12][13][14][15][16][17]. Conversely, for molecules which are already spin polarized in the gas phase, adsorption on a nonmagnetic surface can also result in interesting molecular magnetic properties, e.g., via charge-transfer processes from/towards the molecule and screening effects [16,[18][19][20][21].…”