Random walks based approach to study on molecular structures and torsional barrier heights of hydrogen peroxide

The optimized structures at the equilibrium, cis and trans configurations and the barrier heights for the cis and trans saddle points for hydrogen peroxide, obtained using the diffusion quantum Monte Carlo simulations are reported. The Monte Carlo calculated torsional barriers, ΔEtrans = 386(26) cm−1 and ΔEcis = 2526(41) cm−1 are in very good agreement with experimental values, ΔEtrans = 385/387 cm−1 and ΔEcis = 2488/2563 cm−1.