Can Oxywater Be Made?

Abstract

Ab initio quantum mechanical methods have been applied to an investigation of the oxywater (H 2 OO)-hydrogen peroxide (HOOH) isomerization at high levels of theory. The investigation employed basis sets up to triple-plus double polarization plus f functions (TZ2P+f) and levels of correlation up to coupled cluster including single, double, and perturbatively treated connected triple excitations [CCSD(T)]. Harmonic vibrational frequencies are obtained via finite differences of analytic gradients. Their infrared intensities are also reported. The classical barrier for isomerization of oxywater is substantial (5.7 kcal/mol) at the highest level of theory. Correction for zero-point vibrational energies yields a predicted activation energy of 3.3 kcal/mol. The equilibrium dipole moment of oxywater is predicted to be substantial, namely 4.5 D. Thus, oxywater indeed awaits synthesis.

Complexes and Clusters of Water Relevant to Atmospheric Chemistry: H2O Complexes with Oxidants

“…OÀO-bonded structure R(O···O) = 1.549 DE = 155.2 CCSD(T)/TZ2P + f [44] refs. [38, 40-42, 45, 46] [51] MP4/6-31G(d,p)) partial optimization [47] refs.…”

“…The most reliable confirmation of this fact came from studies by Schaefer and co-workers [43,44] who performed the full geometry optimization of oxywater, hydrogen peroxide, and the transition structure between them at the MP2, MP4, CCSD, CCSD(T), and BD levels in the DZP and TZ2P basis sets. (Hereafter, the DZ, DZP, TZP, and TZ2P + f designate the "double-zeta", "double-zeta + polarization function", "triplezeta + polarization function", and "triple-zeta + two d,p-functions + f-function" basis sets.…”

“…Later, the oxywater structure and energy were also studied using DFT and G2 theory [45] and the results are in good agreement with refs. [43,44].…”

Testing the parametric two-electron reduced-density-matrix method with improved functionals: Application to the conversion of hydrogen peroxide to oxywater

“…24,25 Energies from the M parametrization approach the accuracy of coupled cluster with single, double, and triple excitations at a computational cost of the configuration interaction method with single and double excitations. 25 In this paper we test the parametric 2-RDM method with the M functional by studying the reactions of hydrogen peroxide (HP) to form oxywater (OW) 30 and hydroxyl radicals (HR). Oxywater is an isomer of hydrogen peroxide where both hydrogens are bonded with one of the oxygen atoms.…”

Dynamic molecular oxygen production in cometary comae

“…As the projectile rebounds, the transient state disintegrates, producing an energetic molecular product, H 2 O–O*, in an excited state. We conjecture that this product is the elusive oxywater, a structural isomer of hydrogen peroxide and possible intermediate in oxidation reactions initiated by the latter21. The H 2 O–O* is unstable22 and splits rapidly into a pair of ions, H + and HO 2 − , both of which are observed on FeO x and SiO y (Fig.…”