Sumit Beniwal https://orcid.org/0000-0002-9381-5481
Birgit Weber https://orcid.org/0000-0002-9861-9447
Peter A Dowben https://orcid.org/0000-0002-2198-4710
Axel Enders https://orcid.org/0000-0002-2198-4710
Date of this Version
J. Phys.: Condens. Matter 32 (2020) 324003
The iron(II) spin crossover complex Fe(1,10-phenanthroline)2(NCS)2, dubbed Fe-phen, has been studied with scanning tunneling microscopy, after adsorption on the 'herringbone' reconstructed surface of Au(111) for sub-monolayer coverages. The Fe-phen molecules attach, through their NCS-groups, to the Au atoms of the fcc domains of the reconstructed surface only, thereby lifting the herringbone reconstruction. The molecules stack to form 1D chains, which run along the Au directions. Neighboring Fe-phen molecules are separated by approximately 2.65 nm, corresponding to 9 atomic spacings in this direction. The molecular axis, defined by the two phenanthroline groups, is aligned perpendicular to the chain axis, along the Au  direction, thereby bridging over 5 atomic spacings, in this direction. Experimental evidence suggests that the molecular spins are locked in a mixed state in the sub-monolayer regime at temperatures between 100 K and 300 K.