The gravimetric storage capacity and radial distribution function parameters show that, under the identical temperature and pressure conditions, the magnitude of the hydrogen radial distribution on the C19B surface is larger than that on C19Si and C20. <...> The calculated maximum of the gravimetric storage capacity for C19B at 273 K and 30 MPa is 7.6 %. <...> In general, energy conversion and storage systems require a rather complex combination of materials that can selectively promote an adsorption process with efficiencies close to the thermodynamic limit [ 1 ]. <...> Pure hydrogen can be the final destination in the evolution of fuel usage from coal to petroleum to natural gas, which has followed a trail of increasing hydrogen content [ 2 ]. <...> A major bottleneck for the hydrogen vehicle is the problem of hydrogen storage. <...> Hydrogen has the highest energy per unit mass but occupies a large volume. <...> However, several studies have been performed to meet the goals of the U. S. Department of Energy (DOE) Hydrogen plan, 6.5 wt% (weight percent), most of them have failed to approach the proposed target. <...> Recently, considerable attention has been driven to porous materials such as clathrates, zeolites, carbon nanotubes, and fullerenes as possible materials for hydrogen storage [ 4 ]. <...> The properties of silicon and boron substituted fullerenes have motivated a number of studies in recent years on SiC fullerene and boron fullerene type structures [ 5, 6 ]. <...> Boron and silicon-doped carbon clusters of the types BmCn (m = 1—4) and SimCn (m = 1, 2) have been produced via the laservaporization cluster beam technique [ 7 ]. <...> The Lennard—Jones parameters for the interaction between the gas and fullerene surfaces were calculated using Eqs. (2), (3) [10—12 ]. <...> In our simulations, periodic boundary conditions are imposed in all directions. <...> The cutoff length in evaluating the LJ potential is set to 2.5 Е on all fullerene structures. 2 ij r2 i jr r , ij ij For each calculation, 107 configurations are generated. <...> The initial configurations are discarded to guarantee equilibration, whereas the remaining configurations are used as the average of the desired ensemble properties. <...> The effects of the temperature and pressure on the adsorption phenomena are examined. <...> The aim of the present work is <...>