Co dimers on hexagonal carbon rings proposed as subnanometer magnetic storage bits.

It is demonstrated by means of density functional and ab initio quantum chemical calculations, that transition-metal-carbon systems have the potential to enhance the presently available area density of magnetic recording by 3 orders of magnitude. As a model system, Co2 benzene with a diameter of 0.5 nm is investigated. It shows a magnetic anisotropy of the order of 0.1 eV per molecule, large enough to store permanently 1 bit of information at temperatures considerably larger than 4 K. A similar performance can be expected, if cobalt dimers are deposited on graphene or on graphite.

13C NMR fingerprint characterizes long time-scale structure of Sc3N@C80 endohedral fullerene.

(13)C NMR chemical shifts of Sc(3)N@C(80) were computed using quantum Born-Oppenheimer molecular dynamics simulations, followed by DFT-NMR calculations on a large series of snapshots. Whereas calculations of the C(3) static gas-phase optimized structure fail to reproduce the two-line experimental spectrum, long-time molecular dynamics simulations quantitatively reproduce the experiment.