Verification of DFT-predicted hydrogen storage capacity of VC3H3 complex using molecular dynamics simulations.

Density functional theory (DFT) and Fourth-order Möller-Plesset (MP4) perturbation theory calculations are performed to examine the possibility of hydrogen storage in V-capped VC(3)H(3) complex. Stability of bare and H(2) molecules adsorbed V-capped VC(3)H(3) complex is verified using DFT and MP4 method. Thermo-chemistry calculations are carried out to estimate the Gibbs free corrected averaged H(2) adsorption energy which reveals whether H(2) adsorption on V-capped VC(3)H(3) complex is energetically favorable, at different temperatures. We use different exchange and correlation functionals employed in DFT to see their effect on H(2) adsorption energy. Molecular dynamic (MD) simulations are performed to confirm whether this complex adsorbs H(2) molecules at a finite temperature. We elucidate the correlation between H(2) adsorption energy obtained from density functional calculations and retaining number of H(2) molecules on VC(3)H(3) complex during MDs simulations at various temperatures.