A substantial potential advantage of industrial electric
and thermoelectric
devices utilizing endohedral metallofullerenes (EMFs) is their ability
to accommodate metallic moieties inside their empty cavities. Experimental
and theoretical studies have elucidated the merit of this extraordinary
feature with respect to developing electrical conductance and thermopower.
Published research studies have demonstrated multiple state molecular
switches initiated with 4, 6, and 14 distinguished switching states.
Through comprehensive theoretical investigations involving electronic
structure and electric transport, we report 20 molecular switching
states that can be statistically recognized employing the endohedral
fullerene Li@C60complex. We propose a switching technique
that counts on the location of the alkali metal that encapsulates
inside a fullerene cage. The 20 switching states correspond to the
20 hexagonal rings that the Li cation energetically prefers to reside
close to. We demonstrate that the multiswitching feature of such molecular
complexes can be controlled by taking advantage of the off-center
displacement and charge transfer from the alkali metal to the C60cage. The most energetically favorable optimization suggests
1.2–1.4 Å off-center displacement, and Mulliken, Hirshfeld,
and Voronoi simulations articulate that the charge migrates from the
Li cation to C60fullerene; however, the amount of the
charge transferred depends on the nature and location of the cation
within the complex. We believe that the proposed work suggests a relevant
step toward the practical application of molecular switches in organic
materials.