Verification of DFT-predicted hydrogen storage capacity of VC _3H_3 complex using molecular dynamics simulations

摘要

Density functional theory (DFT) and Fourth-order M?ller-Plesset (MP4) perturbation theory calculations are performed to examine the possibility of hydrogen storage in V-capped VC_3H_3 complex. Stability of bare and H_2 molecules adsorbed V-capped VC_3H_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_3H_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 _3H_3 complex during MDs simulations at various temperatures.