Differential charge diagrams were also plotted and are shown in Fig. 10.
The yellow regions between the Li and H2 showing
electron depletion and blue regions near H2 showing
electron accumulation confirm that there is electronic charge transfer
between the two species. It can be inferred that the electronic charge
transfer with H2 is primarily limited to just the
lithium atom. This is primarily due to the cationic nature of the Li
atom. The side view of the charge diagrams in the Li decorated SV
silicene system shows that the electron accumulation and electron
depletion regions surrounding both the H atoms in the H2molecule are symmetric in nature while Li decorated SW silicene shows
slightly asymmetric regions. The electron accumulation regions at the
Li-Si bonds indicate that charge is transferred from the substrate to
the Li atom thus playing an indirect role in hydrogen adsorption.
Similar charge distribution was also observed in the case of
H2 adsorption onto Li decorated SW silicene with an
indirect
contribution
towards hydrogen storage coming from the defected silicene substrate as
well.
Fig 10. Charge
Density diagram of a) H2 absorbed Li decorated SV
Silicene and b) H2 absorbed Li decorated SW Silicene.
Yellow regions and blue regions are representative of electron depletion
and electron accumulation respectively. The isosurface level has been
set as 0.00015000 e/Å3.