An ab initio study on the equilibrium structure and torsional potential energy function of hydrogen peroxide

The molecular parameters of hydrogen peroxide, H2O2, have been determined in large-scale ab initio calculations using the coupled cluster method, CCSD(T), and basis sets of double- to quadruple-zeta quality. With the largest basis set employed, cc-pVQZ, the equilibrium parameeters are determined to be: r(OO) = 1.4525 Å, r(OH) = 0.9627 Å, < (OOH) = 99.91°, <(HOOH) = 122.46°, Vtrans = 377 cm−1 and Vcis = 2545 cm−1.