Investigating the Ground-State and Ionization Processes of Hydrogen Peroxide Dimers Using Sequentially Combined Theoretical Approaches

TL;DR

This paper studies the structures and ionization energies of hydrogen peroxide dimers using advanced theoretical methods to better understand their properties and guide future experiments.

Contribution

The study introduces a combined theoretical approach to analyze hydrogen peroxide dimer conformations and their ionization processes.

Findings

All stable conformations are within 10 kJ/mol of the most stable structure.

The first ionization energy of conformation I is 11.72 eV, and for conformation V it is 11.58 eV.

The results may help in assigning experimental observations of hydrogen peroxide clusters.

Abstract

We present a study of the structures and ionization energies
(IEs)
of a series of conformations of hydrogen peroxide (H2O2) dimers. Ground-state properties were computed using the
coupled-cluster with single, double, and perturbative triple excitations,
CCSD­(T), method with large correlation-consistent basis sets, while
the ten lowest-lying IEs of the H2O2 dimer conformations
were determined through the use of the equation-of-motion ionization
potential coupled-cluster with single and double excitations method
(EOMIP-CCSD) combined with correlation-consistent basis sets, extrapolation
to the complete basis set limit, and consideration of core-correlation
effects. All of the stable conformations were determined to be within
10 kJ/mol of the most stable structure (conformation I). The first
IE of conformation I was determined to be 11.72 eV, while the corresponding
value for conformation V was calculated as 11.58 eV. This difference
(which was also noticed for other low-lying IEs and conformations)
may be helpful for the assignments of experimental results. Given
that the H2O2 clusters were first isolated through
the use of beam experiments in the recent years, it is expected that
the present work can call the attention of the community. In addition,
the use of the combined theoretical approaches employed regarding
the selection of the relevant conformations and the exploration of
the corresponding ionization processes for the molecular clusters
may present an initial guide for researchers venturing into the field.

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