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Study of the Electronic Structure of Alkali Peroxides and Their Role in the Chemistry of Metal-Oxygen Batteries.

ABSTRACT: We use a multiconfigurational and correlated ab initio method to investigate the fundamental electronic properties of the peroxide MO₂^- (M = Li and Na) trimer to provide new insights into the rather complex chemistry of aprotic metal-O₂ batteries. These electrochemical systems are largely based on the electronic properties of superoxide and peroxide of alkali metals. The two compounds differ by stoichiometry: the superoxide is characterized by a M⁺O₂^- formula, while the peroxide is characterized by [M⁺]₂O₂^2-. We show here that both the peroxide and superoxide states necessarily coexist in the MO₂^- trimer and that they correspond to their different electronic states. The energetic prevalence of either one or the other and the range of their coexistence over a subset of the MO₂^- nuclear configurations is calculated and described via a high-level multiconfigurational approach.

SUBMITTER: Pierini A

PROVIDER: S-EPMC8558866 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Study of the Electronic Structure of Alkali Peroxides and Their Role in the Chemistry of Metal-Oxygen Batteries.

Pierini Adriano A Brutti Sergio S Bodo Enrico E

The journal of physical chemistry. A 20211014 42

We use a multiconfigurational and correlated ab initio method to investigate the fundamental electronic properties of the peroxide MO2- (M = Li and Na) trimer to provide new insights into the rather complex chemistry of aprotic metal-O2 batteries. These electrochemical systems are largely based on the electronic properties of superoxide and peroxide of alkali metals. The two compounds differ by stoichiometry: the superoxide is characterized by a M+O<su ...[more]

PMID: 34649438

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