posted on 2024-01-08, 05:47authored byAlain Rochefort, Khalid N. Anindya, Xavier Bouju, Adam H. Denawi
The
interaction of a 2D metal–organic network (MON) stacked
on graphene has been studied with the help of first-principles density
functional theory (DFT) and DFT + U calculations.
By varying the length of a polyphenyl-dicarbonitrile linker, we have
evaluated the influence of the metal–metal distance on the
electronic and magnetic properties of the MON complexes. Although
MON composed of small molecules shows a moderately stable ferromagnetic
phase, this magnetic order drops with the size of the complex. After
the adsorption of MON on graphene, this last becomes n-doped due to
an important charge transfer that improves with the molecular unit
size. The MON–graphene interaction contributes to drastically
reduce the overall stability of any magnetic order, but the local
charge transfer remains strongly spin-polarized-dependent. Hence,
the adsorption of magnetic MON on graphene leads to the modification
of the electronic and magnetic properties of graphene, mostly in a
closed proximity region to the active metal atoms of the MON. Spin-polarized
scanning tunneling microscopy simulations reveal a magnetic signature
in graphene that originates from its interaction with the MONs and
that could be experimentally observed.