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Oxygen Atom Stabilization by a Main-Group Lewis Acid: Observation and Characterization of an OBeF₂ Complex with a Triplet Ground State.

ABSTRACT: Terminal oxygen radicals involving p- and d-block atoms are quite common, but s-block compounds with an oxygen radical character remain rare. Here, we report that alkaline-earth metal beryllium atoms react with OF₂ to form the oxygen beryllium fluorides OBeF and OBeF₂. These species are characterized by matrix-isolation infrared spectroscopy with isotopic substitution and quantum-chemical calculations. The linear molecule OBeF has a ²Π ground state with an oxyl radical character. The ³A₂ (C_2v) ground state of OBeF₂ represents the unusual case of a triplet oxygen atom stabilized by a relatively weak interaction by the Lewis acidic BeF₂. The interaction involves both a donor component from oxygen to empty Be orbitals and a back-bonding contribution from fluorine substituents toward oxygen.

SUBMITTER: Deng G

PROVIDER: S-EPMC11363016 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature

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Oxygen Atom Stabilization by a Main-Group Lewis Acid: Observation and Characterization of an OBeF2 Complex with a Triplet Ground State.

Deng Guohai G Reimann Marc M Meyer Deniz D Xia Xiya X Kaupp Martin M Riedel Sebastian S

Journal of the American Chemical Society 20240815 34

Terminal oxygen radicals involving p- and d-block atoms are quite common, but s-block compounds with an oxygen radical character remain rare. Here, we report that alkaline-earth metal beryllium atoms react with OF2 to form the oxygen beryllium fluorides OBeF and OBeF2. These species are characterized by matrix-isolation infrared spectroscopy with isotopic substitution and quantum-chemical calculations. The linear molecule OBeF has a 2Π ground state with an oxyl r ...[more]

PMID: 39147578

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