Quantum chemical studies on beryllium hydride oligomers

The present study explores electronic and structural properties, ionization potential (IP), electron affinity (EA), polarizability ({\alpha}), chemical potential (\mu), hardness ({\eta}), softness (S), band gap ({\Delta}E(HOMO-LUMO)) and spectral characteristics of beryllium hydride oligomers by quantum chemical treatment. The discrepancies in the calculated reactive descriptors of molecules are presumably due to variations in electron distribution and spin pairing near Fermi level. The molecules BeH2, Be3H5, Be5H10, Be7H14 and Be9H18 have been found to be more stable than Be2H4, Be4H8, Be6H12, Be8H16 and Be10H20. Ultra-soft pseudopotentials for electron-nuclei interactions with local density approximation (LDA) and generalized gradient approximation (GGA) have been used to understand the nature of bonding in crystalline beryllium hydride. The observed band gap value of crystalline BeH2 is comparable with the band gap value of beryllium hydride oligomers