Modelling doped (Ni, Pd, Pt) sulfur–nitrolic systems as new motifs for storage of hydrogen

Abstract

Quantum chemical calculations have been performed on a series of cyclic rings (S₂N₂ and S₃N₃⁻) with and without doping of transition metals (TM = Ni, Pd and Pt) to study their ability to store hydrogen. Calculations show that S₂N₂ is planar while S₃N₃⁻ is puckered to C_3v symmetry. Undoped SN rings and chains are predicted to have dispersive interactions with H₂ with endothermic binding energies and significant contributions from entropy at room temperature. However, doping with TM increases the number of binding hydrogens. Binding of the TM with the rings shows interesting diversity in structures. Strategies are proposed for the storage of hydrogen in this interesting class of molecular materials.